A bomb attack in Yemen is reported to have killed three policemen and wounded four civilians.
The bomb exploded as they were parking their car in the city of Maareb, about 105 miles (170 km) east of the Yemeni capital, Sanaa.
Witnesses said the vehicle was totally destroyed by the blast.
The bombing follows a series of similar attacks in recent weeks, aimed at government, foreign diplomatic and commercial targets.
Foreign tourists come under regular attack in Yemen - attacks often claimed by al-Qaeda.
The US embassy in Sanaa said last week it was ordered by the state department to evacuate non-essential personnel.
In 2000, al-Qaeda targeted the navy destroyer USS Cole in the southern port of Aden, using a small boat packed with explosives to blow a hole in the side of the vessel, killing 17 American sailors.