KABUL, Afghanistan — The police chief of a volatile Afghanistan district was killed by a roadside bomb on Thursday, officials said, just two weeks after taking over for his predecessor, who was killed in the same manner.

It was the third such killing of a security chief in the district — Jaghatu, in southeastern Afghanistan — in about a month, underscoring the continuing high casualties Afghan forces are suffering in defending against a resurgent Taliban. Their predecessor was killed in a Taliban ambush.

Although Afghan security forces have denied the Taliban major victories in recent months, bloody local skirmishes continue, and military officials say the country’s forces are engaged in fighting in 20 of the country’s 34 provinces.

The government does not release official casualty tallies of its forces, but senior officials say this year’s figures have matched, and at times exceeded, the record numbers for 2016, when about 6,300 members of Afghan forces were killed and close to 12,500 were wounded.