Baghdad  - Three people were killed and 15 others were injured by a bicycle bomb in Baquba, the capital of the ethnically divided Iraqi province of Diyala, police said Monday.

All the casualties were construction workers looking for day jobs, police in Baquba told the German Press Agency dpa on Monday.

Divided between concentrations of Kurds in the north, Shiite Muslims along its border with Iran, and Sunni Muslims in the south-west, Diyala has been the site of deadly clashes between rival militias and insurgent groups for years.

To the north of the country, attacks targeting police and government officials continued in and near the city of Mosul on Monday.

Two Iraqis were killed and another five were wounded in two separate attacks in and near the city, some 400 kilometres north of Baghdad, police there told dpa.

One Iraqi policeman was killed and four people were wounded when a bomb exploded as a police patrol passed through western Mosul's al-Yarmuk district on Monday.

Not long after, unidentified gunmen fatally shot the director of Mosul's Office of Immigrant Affairs north of the city and injured his assistant, police said.

Mosul, the capital of Iraq's Nineveh province, remains among the most dangerous cities in Iraq. Iraqi forces, backed by US troops, have been waging an intensified campaign to arrest insurgents holed up in the city, but insurgents have responded with near-daily, deadly attacks.

The attacks in Iraq's east and north highlighted the continuing unrest in the country as British troops prepare to leave.

On Monday, Baghdad's Voices of Iraq news agency, citing "a highly-placed official" from the airport in the southern Iraqi city of Basra, reported that British troops would formally hand over control of the British base next to the airport to US soldiers in a ceremony on Tuesday.

Iraq and Great Britain signed a deal last year whereby some 4,100 British troops will remain in Iraq to train the Iraqi army before British forces withdraw completely in July 2009.

After the United States, Britain sent the most soldiers to support the 2003 invasion of Iraq.

British troops transferred the responsibility of operating Basra's civilian airport to Iraqi authorities on January 1, but the British military retained control of the military base next to the airport. Control of that base will now pass to the US military.

Though calm has largely returned to Basra, the base has frequently been the target of rocket attacks. (dpa)