In the three documents, the investigators have held the same people responsible for the January 27 grenade attack that killed former finance minister Shah AMS Kibria and five others. But they failed to identify the mastermind of the attack and the source of the grenade, as well.

The chargesheet in the Kibria killing case accused 10 BNP men of the assassination and named BNP leader Abdul Quaiyum, who was later expelled, as the one to have orchestrated the assassination. The chargesheet was filed on March 20, six days after the government investigation report was submitted.

The investigators, however, were mandated to find the mastermind and perpetrators of the murder.

Kibria's family had dismissed the local investigations saying the local investigators were not allowed to work freely and interrogate powerful individuals who might have been behind the killing.

In the other case, filed under the Explosives Substance Act, the investigation officer pressed charges against the same 10 people on April 20 but he could not put his finger on the source of the grenade, which was the main task of the investigator.

Habiganj district Awami League Organising Secretary Abdul Majid Khan, who filed the two cases, told The Daily Star yesterday, "I do not know what is there in the report of the government-instituted probe committee, but I reckon the officers investigating the two cases ran their enquiry in line with the guidelines of the that probe committee."

There is negligible difference in the contents in these three documents.

The chargesheet in Kibria killing case investigated by Munshi Atiqur Rahman, senior assistant superintendent of police at the Criminal Investigation Department (CID), pointed out that BNP leader Quaiyum had planned the killing and supplied the grenade.

But his report did not mention anything about how he had obtained the grenade or who has been backing Quaiyum in such a high-profile crime.

Quaiyum have not yet given any confessional statement and he still claims to be innocent. Investigators say they named Quaiyum on the basis of statements of the other accused.

The chargesheet in the other case investigated by Officer-in-Charge of Habiganj Sadar Police Station Shafiuzzaman, however, added a new information. It said Quaiyum collected the grenade from Chunarughat area, without mentioning who supplied the grenade.

Earlier, the government investigation report had mentioned that the grenade might have been brought from the frontier area of Sylhet.

All the three documents say that the motive behind the killing was election politics. Kibria was killed to ensure that Quaiyum is elected from the constituency (Habiganj-2) in the upcoming election, although Quaiyum is not a potential candidate.

The documents say Quaiyum assumed that the potential local BNP candidates Abu Leis Mobin Chowdhury, GK Gaus and Ashraful Bari Noman would have been blamed for the killing and that would have cleared his way to be a candidate of the ruling party.

Such similarities in the three reports have raised questions whether the two chargesheets just followed the government investigation report or whether the investigators of the two cases independently made similar conclusions.

When asked, an official involved in the government investigation said, "There may be some similarities. When we were investigating, CID officials were doing their investigation simultaneously. But we worked independently."

Legal expert Shahdeen Malik expressed his doubt about the integrity of the investigators. He said it seems that the chargesheeted persons were involved in the crime, but crimes of such magnitude are supposed to have involvement of much more influential persons.

"But not a single influential person has ever been found to be involved in these and other arms and explosives related cases," he said. "This seems highly improbable."

Another legal expert seeking anonymity raised the question of authenticity of the investigations. He said the failure of the investigators to identify the mastermind and find out the source of the grenade has damaged the merit of the probes.

However, Munshi Atiqur Rahman of CID told The Daily Star, "I have not even seen the government investigation report as I thought that might influence our work."

Investigation officer in the explosive substance case Shafiuzzaman said, "There was only one incident. It is natural to have some similarities." He however said, "You cannot say both the chargesheets are the same."

When asked whether his chargesheet has any acceptability since he failed to pinpoint the source of the grenade, Shafiuzzaman said he had mentioned that Quaiyum brought the grenade.

On another question on the source of the grenade, Shafiuzzaman said, "Quaiyum would not say anything about grenade. He has not given a confessional statement. But his accomplices said that Quaiyum brought the grenade from Chunarughat."

Asked if he will continue investigation to find the source of the grenade, he said, "I have concluded my investigation. I have even talked to the FBI and asked them if they have any information on the source of grenade. They said they do not have any information."

When asked if Munshi Atiqur makes further investigation to find the mastermind of the killing, he said, "If we get further evidence, we may submit a supplementary chargesheet."

About the mastermind of the attack, both Munshi Atiqur and Shafiuzzaman said their investigations have found no-one whom Quaiyum may have received orders from.

The investigators said Quaiyum's 12 bank accounts had unusually high transactions. After freezing these accounts, the CID is now investigating the matter to find out the source of his money. The CID remains tight-lipped about the parties with whom Quaiyum had transactions.

"We are considering filing a case against him under the Money Laundering Act after our investigation ends," said a CID source.

A section of newspapers have reported that the chargesheets mentioned Quaiyum's link with international terrorists like Osama bin Laden but Shafiuzzaman said, "This is not true. We suspect he may have such links. But unless we have some evidence, we cannot say."

Meanwhile, one of the 10 accused in the case, Jainul Abedin Mumin, who confessed to have thrown the grenade, has agreed to be the approver in the Kibria killing case. Police said Mumin has filed a prayer to that end to the government, which is now under consideration.