The militant Islamic State group has claimed responsibility for a series of deadly bombings targeting Taliban vehicles in Jalalabad, Afghanistan.

At least eight people, including several Taliban fighters, were killed in the attacks on Sunday and Saturday in the provincial city of Jalalabad — an IS stronghold.

The claim, published late Sunday on the militant group’s media arm, the Aamaq news agency, signals a growing threat to the Taliban by their long-time rivals.

The Taliban seized control of Afghanistan in a blitz campaign last month, overrunning the capital of Kabul while the US and North Atlantic Treaty Organisation (Nato) were in the final phase of withdrawing their troops. The last foreign soldiers left on Aug. 30.

The Taliban now face major economic and security challenges in trying to govern Afghanistan, and an accelerated campaign of IS attacks will further complicate those efforts.

The Taliban and IS militants were enemies before foreign troops left Afghanistan.

Differences over religion and strategy have led to bloody fighting between the Taliban and IS.

Saturday’s bombing came as the Taliban ordered boys and male teachers to return to secondary school in Afghanistan — but girls were excluded.

“All male teachers and students should attend their educational institutions,” a Taliban statement had said ahead of classes resuming on Saturday, the first day of the week in Afghanistan.

The statement, issued late on Friday, made no mention of women teachers or girl pupils.

Since a US-led invasion ousted the Taliban in 2001, significant progress has been made in girls’ education, with the number of schools tripling and female literacy nearly doubling to 30 per cent.

However, the change was largely limited to the cities. The United Nations said it was “deeply worried” for the future of girls’ schooling in Afghanistan.