JALALABAD, Afghanistan — A spring offensive by Taliban insurgents has resulted in a series of attacks across Afghanistan, killing about 100 soldiers and police officers in the past week, according to officials. In the latest attack, on government offices in the eastern city of Jalalabad on Sunday, at least 12 people were said to have been killed.

In a separate episode, an Afghan military helicopter crashed early Sunday morning in the southern province of Helmand, and Taliban insurgents posted video of the mangled remains, claiming to have shot it down.

In Zabul Province, also in the south, a week of heavy fighting left 70 police officers dead, local officials said. In Farah Province, in the west, at least 15 officers were killed in four recent attacks, according to provincial officials. And in the northern province of Baghlan, a senior security official said that at least 44 soldiers and police officers were killed last week when insurgents seized control of a district government compound.

The increased tempo of attacks appeared to be part of an offensive announced by the Taliban on April 25 in a statement rejecting recent government peace overtures.