Neighbours and relatives, including an uncle, said Dwayyat was divorced from a Jewish Israeli. Police said he had a history of drug offences but no known political affiliation.
Dwayyat drove the 20-tonne earthmoving vehicle for 500 metres (yards) along Jaffa Road, rolling over cars, crushing some occupants, and ramming into a crowded number 13 bus, flipping it on its side with his mechanical shovel.
Dramatic television footage showed the vehicle later at a standstill and a policeman in the cab, as rescue workers and passersby surveyed the wreckage. However, the bulldozer started moving again and a struggle could be seen inside the cab.
An Israeli baby is evacuated from the scene of an attack in Jerusalem July 2, 2008. A Palestinian construction worker rammed an earthmoving vehicle into buses and cars on one of west Jerusalem's busiest streets on Wednesday, killing three Israelis and wounding more than 40 before he was shot dead. [Agencies]
A man in civilian clothes leapt aboard and fired a pistol into the cab, followed by a helmeted policeman in body armour who fired an automatic rifle. The officer later said he fired twice at the wounded driver to ensure he was no further threat.
"The only way to stop him was with a bullet to the head," witness Moshe Oren said afterwards, "We were relieved."
Israeli government spokesman Mark Regev said the attack "was an act of senseless, murderous violence". An aide to Abbas called it an attempt to wreck peace negotiations and urged Israel to show restraint in its response.
Abbas's opponents in Hamas and Islamic Jihad said the attack was a "natural" response by Palestinians to Israeli aggression but, nearly two weeks into a truce in the Gaza Strip, neither Islamist group said it was responsible for the incident.
US President George W. Bush called Olmert to offer condolences, Israeli spokesman Regev said.
Medical officials said more than 40 people were taken to hospital. Police at first identified the dead as two Israeli men and a woman, but then corrected this to one man and two women.