MANILA — A Philippine mayor was fatally shot Tuesday afternoon, one day after a gunman killed another mayor who was publicly supportive of President Rodrigo Duterte’s unrelenting war on the drug trade.

Ferdinand Bote, 57, the mayor of General Tinio, a municipality about 50 miles north of Manila, was in his car when a lone assailant on a motorcycle attacked him, the police said in a statement. Mr. Bote sustained several gunshot wounds to his body and was later pronounced dead at a hospital.

It was not immediately clear why Mr. Bote was attacked.

The killing happened a day after Antonio Halili, the mayor of Tanauaun, about 40 miles south of Manila, was killed by a sniper at a flag-raising ceremony. Mr. Halili was known for parading criminal suspects around his city to shame them, but he was himself later accused of dealing drugs.

Mr. Bote was the fifth Philippine mayor killed during Mr. Duterte’s war on the drug trade, which has led to the deaths of thousands of people and drawn condemnation from rights groups. Three of the mayors were on the president’s list of 150 Philippine officials — including mayors, judges and police officers — whom he had accused of being involved in drugs.