An Afghan judge was shot dead in an ambush in the eastern city of Jalalabad Wednesday, police said, the third court official killed in less than a month.

Judge Hafizullah was attacked as he headed to work in a motor trishaw, said Farid Khan, spokesman for Nangarhar province's police.

Gulzada Sangar, a doctor at Jalalabad public hospital, said Hafizullah had multiple bullet wounds.

The murder of Hafizullah, who like many Afghans goes by just one name, comes after militants shot dead two women judges working for the Supreme Court in Kabul on January 17.

Several prominent Afghans -- including judges, clerics, journalists, activists and doctors -- have been assassinated in often brazen daytime attacks.

Targeted killings with remotely detonated bombs attached to vehicles, or drive-by shootings, have become favoured tactics of insurgents, especially during the morning commute in big cities.

Earlier Wednesday a policeman was killed and three others wounded in Kabul by a bomb attached to their vehicle.

Four similar bomb blasts rocked the Afghan capital on Tuesday, including one that killed a prominent cleric.

The murder of cleric Mohammad Atif was later claimed by the jihadist Islamic State group, according to the SITE monitoring group.

IS has claimed some of the target killings in the Afghan capital, but government officials blame the Taliban for the murders.

Separately, four security personnel were killed overnight by a car bomb at a military base in the restive southern province of Uruzgan, governor Mohammad Omar Shirzad told reporters.

Deadly violence has surged across Afghanistan in recent months despite ongoing peace talks between the Taliban and government.