DHAKA: US-led air strikes have disrupted Islamic State (IS) militants but the fight against them will take years.

A Pentagon spokesman has told the BBC.

The comments came as activists reported new strikes around the town of Kobane, near Syria's border with Turkey.

Kobane has been besieged by IS fighters for several days, forcing about 130,000 Syrian Kurds to flee into Turkey.

IS has seized large areas of Syria and Iraq, and the US has launched nearly 200 air strikes in Iraq since August.

However, Monday’s strikes expanded the anti-IS campaign across the border into Syria for the first time.

Activists say at least 70 IS militants, 50 other al-Qaeda-linked fighters and eight civilians were killed in the strikes, which hit multiple targets in the north and east of Syria.

Speaking in Washington, Rear Adm John Kirby said the air strikes in Syria had successfully degraded IS capabilities.

‘We think we have hit what we were aiming at,’ he said.

However, IS was good at adapting and reacting to changes, he said, adding that the group presented a ‘serious threat’ that would not be eliminated ‘within days or months’.

‘It’s going to take a serious effort by all involved. We do believe that we’re talking about years here.’

BDST: 1502 HRS, SEP 24, 2014