Kidnappers who seized Egypt's envoy to Baghdad over the weekend have yet to make contact with the authorities or present any demands, Egyptian and Iraqi officials said yesterday.

More than 36 hours after Ihab el-Sherif was snatched by gunmen off a Baghdad street, no group had claimed responsibility for the kidnapping.

The US military meanwhile announced the arrest of a Tunisian suspected of bringing more than 100 suicide bombers into Iraq on behalf of al-Qaeda.

No group has yet claimed responsibility for the abduction of Ihab al-Sharif, who was set to become the first Arab ambassador to Iraq since the fall of Saddam Hussein's regime in March 2003.

The Egyptian government appealed for the swift release of the 51-year-old father of two.

US and Iraqi soldiers scoured the restive districts west of the airport, including the Al-Jamiaa neighbourhood where Sharif was abducted.

"Soldiers are conducting offensive operations against terrorist safe havens on the west side of Baghdad International Airport," Sergeant David Abrams of the US military told AFP.

He said several suspects had been detained so far but declined to give details. Three Iraqis were killed and three wounded in two roadside bombing in west and south Baghdad, the interior ministry said.

Meanwhile, the US-led military coalition in Iraq could begin handing over security responsibility to Iraqi forces within a year, even though the insurgency could go on for some time, British Defence Secretary John Reid said yesterday.

"The insurgency in Iraq may go on for some considerable time. But there is a second question and that is: Who will lead the security efforts against the insurgency?" Reid told BBC radio.