Abu Ahmed Jayed An Rabbi filed the case with Gulshan police station against Koko and his two brothers-in-law Mustaqin Reza and Muktaqin Reza, accusing them of extorting a total of Tk 1.20 crore over a period of a few years.

In the case statement Rabbi, the proprietor of an advertising firm, Add Media Ltd, mentioned that Koko along with his two brothers-in-law came to his office at Gulshan-1 on April 27, 2004.

On arrival, Koko asked Rabbi to appoint his two brothers-in-law as directors of Rabbi's company. As Rabbi declined to appoint them as directors, Koko threatened him with dire consequences. A frightened Rabbi sought three days to deliberate on the matter, the complainant said in the first information report (FIR).

He also alleged that three days later Mustaqin Reza and Muktaqin Reza were appointed as directors of the firm without any investment and since then they withdrew Tk 50,000 each as their monthly salaries from the firm. Koko also received Tk 1 lakh every month from the firm, the complainant said accusing Koko, Mustaqin and Muktaqin of extorting him.

Rabbi mentioned in the case that there was a clear indication that if he would not comply with Koko's proposal his life would be in danger.

In the FIR Rabbi also mentioned that apart from the amount taken from his firm as salaries, Koko took Tk 2 lakh on May 1, 2003, Tk 6 lakh on August 10, 2004, Tk 3 lakh on October 31, 2005, and Tk 2 lakh on January 9, 2006 from him.

"We will take actions after proper investigation," Obaidul Haque, officer-in-charge of Gulshan police, told reporters last night.

Mahbub Morshed, the second officer of the police station said, "Abu Jayed An Rabbi filed an extortion case against Koko."

Although former prime minister Khaleda Zia was scheduled to leave the country for Singapore for treatment along with seven members of her family and house staff last night, she once again abruptly cancelled her trip after hearing about the case filed against her younger son.

Meanwhile, Speaker Barrister Jamiruddin Sircar met the former premier in her cantonment residence last night while the military police check-post at the entrance of the cantonment barred relatives of Khaleda from entering the area.

Sources said the joint forces released Koko on April 16 following his arrest, on conditions that he would not receive any phone call and would not try to contact anybody outside the cantonment residence -- promises he failed to keep.

Although Khaleda Zia agreed to leave the country after Koko had been released but her son's alleged reneging on the promises prompted the government authorities to slap a ban on any foreign trip by him.

According to the sources, Khaleda Zia was supposed to leave the country last night along with Koko, his wife Sharmila Rahman, their daughters Zafira and Zahia, Khaleda's nephew Duke, and two domestic helps at 11:50pm last night on board a Singapore Airlines flight.

But, BNP leader Emran Saleh Prince told The Daily Star at 8:18pm yesterday, "We don't know anything yet."

Sources said Khaleda was interested in going to Singapore not only for treatment but also to ensure a safe passage for her son Koko out of the country, as many allegations are being raised against him.

The government now has some reservations about letting Koko leave the country while Khaleda Zia do not want to leave the country without him as she fears he will also meet the fate of his brother Tarique Rahman, if he continues to stay in the country.

Earlier, Tarique was asked to leave the country but he did not agree, the source said.

Although BNP leaders officially said Khaleda would return to the country soon along with her family members, surprisingly Koko's daughters received transfer certificates from their school, the sources said adding that both the kids have been absent from the school since last month.

Tight security was visible at Zia International Airport last night again in anticipation of the former premier's arrival there to board a flight to Singapore. The authorities assembled a huge number of Rab, police, BDR, and armed police personnel there. The law enforcers were seen restricting entry of people on the approach road to the airport.

According to the sources, Khaleda and Koko did not contact any doctor in Singapore yet, they did not even seek any appointment with any doctor although BNP Joint Secretary General Nazrul Islam Khan on Tuesday said both of them would go to Singapore for treatment.

BNP sources said only party leaders got the permission to see their party chief off while some of Koko's in-laws also had tried to get the same permission.

BNP leaders said Khaleda Zia had always been determined not to leave the country but she changed her mind after her younger son Koko had been picked up by the joint forces during an early morning raid on April 16.

Sources said according to Khaleda Zia's travel plan she and her family would stay in a hotel in Singapore for the first few days and later she would move to a former BNP minister's house there. If not, she would stay in former finance minister Saifur Rahman's youngest son Babu's house. Babu is a close friend of Koko and also a son-in-law of former minister Chowdhury Kamal Ibne Yusuf.

Khaleda's brother Shameem Iskandar's brother-in-law Shahed has a house there and the former premier could also stay there if she wanted, the sources said.

In absence of Khaleda Zia, housekeeper Yunus had the permission to stay in Khaleda's cantonment residence although BNP had already urged the government to ensure security for the former premier's residence as her elder daughter-in-law Dr Zobaida Rahman and her daughter Zaima would also stay there.

The party sources said Zobaida would move to her mother's Dhanmondi residence soon as she had been asked by the authorities not to stay in the cantonment residence in absence of Khaleda, although Zobaida wanted to stay in her mother-in-law's residence.

The house was allotted to late president Ziaur Rahman when he was the deputy chief of army staff soon after the independence. He continued to live there as the army chief, and also as the chief martial law administrator, and then as the president of the country.

After his assassination in 1981, the erstwhile government led by late justice Sattar gave the house to late Ziaur Rahman's family in exchange for a nominal price. Since then, Khaleda and her family have been living there. Khaleda Zia became the prime minister of the country three times but never moved from the house.

The BNP chairperson postponed her suddenly scheduled departure to Singapore once earlier on Monday although preparations had been underway to board her on a flight that night also.

On Tuesday BNP Joint Secretary General Nazrul Islam Khan formally announced that his party chairperson along with some of her family members would soon go to Singapore for treatment and would return by the end of the month.

The party on the same day also notified the government officially of the matter through a letter, seeking permission for the presence of its 15 leaders at the airport to see off the former premier, and urging to ensure security for her cantonment residence during her stay abroad.