A bomb attack on a tourist bus in the Sinai peninsula has killed at least two South Korean tourists and an Egyptian driver, Egyptian police have said.

A number of South Koreans were also hurt in the attack, which came after the bus crossed into Egypt from Israel.

The police said the blast was caused by a roadside bomb or a car bomb. No group has said it carried out the attack.

The Sinai peninsula has become increasingly lawless since Hosni Mubarak was overthrown in 2011.

Officials in Sinai said the bomb blast had killed at least two South Korean tourists and the bus driver.

At least 14 other South Koreans were wounded.

The bus was reported to be heading to St Catherine's monastery, a popular tourist destination near Mount Sinai.

A number of militant groups operate in the area, and Bedouin tribes live largely outside of the control of Cairo.

Attacks by Islamist militants have intensified since the army overthrew President Mohammed Morsi in July.

Morsi appeared in court on Sunday to face charges of espionage and conspiring to commit acts of terror.

The Islamist former leader is facing four separate trials, three of which have now opened.