The toll from the attack at the Yemen Police College increased to 37 dead and 66 wounded, a security official said on Wednesday.
"Some of the victims were badly wounded and are still in intensive care units which means the death toll could rise further," Al-Qadasi, deputy police director in the capital city of Sanaa, told state media.
The victims were members from the police departments lining up at the western gate to register at the college for their promotion, he said.
"Preliminary investigations showed a small pick-up laden with explosives was detonated at the students at 7:00 am," he said, pointing out eyewitnesses saw the driver and his accomplice ran away after they had parked the pick-up at the college.
At the southern gate, high school students were lining up to enroll into the college, Al-Qadasi said, adding, "but these students were away from the incident".
So far, the authorities identified most of the victims except six bodies, he said.
The attack bore the hallmarks of Al-Qaeda and a hunt has been launched for those who carried it, he said.
The bombing was the latest in a series of blasts in Yemeni cities mostly against security and military officers, personnel and installations including the Police College since 2011.
Lately, bombings have started to target Houthi militants who seized the capital and power in September.