Turkey's president said Kobane was "about to fall" after IS fighters advanced into the south west of the Syrian Kurdish town, pressing home a three-week assault that has cost a reported 400 lives.
The prospect that the town on the Turkish border could be captured by the militants has increased pressure on Turkey, with the strongest army in the region, to join the US-led anti-IS coalition, according to Reuters.
IS wants to take Kobane in order to strengthen its grip on the border area and consolidate the territorial gains it has made in Iraq and Syria in recent months. US-led air strikes have so far failed to prevent its advance on Kobane.
Turkish President Tayyip Erdogan said bombing was not enough to defeat IS and Turkey had made clear that additional measures would be needed.
"The problem of IS ... cannot be solved via air bombardment. Right now ... Kobane is about to fall," he said during a visit to a camp for Syrian refugees.
"We had warned the West. We wanted three things. No-fly zone, a secure zone parallel to that, and the training of moderate Syrian rebels," he said.
> Turkey Inaction
He said Turkey would intervene if there were threats to Turkish soldiers guarding a historic site in Syria that Ankara regards as its territory. But so far Turkey has made no move to get involved in the fighting across the border.
From across the Turkish border, two IS flags could be seen flying over the eastern side of Kobane. Two air strikes hit the area and sporadic gunfire could be heard.
The so-called Syrian Observatory for Human Rights monitoring group said it had also documented 412 deaths of civilians and fighters during the three-week battle for Kobane.
On Tuesday, plumes of white smoke rose over eastern and central parts of Kobane and two ambulance crossed the border, travelling from Kobane to the Turkish side.
IS fighters were using heavy weapons and shells to hit Kobane, senior Kurdish official Asya Abdullah told Reuters from inside the town.
“Yesterday there was a violent clash. We have fought hard to keep them out of the town,” she said by telephone. “The clashes are not in the whole of Kobani, but in specific areas, on the outskirts and towards the centre.”
> Ineffective Air Strikes
The IS, an al Qaeda offshoot, has ramped up its offensive in recent days against the mainly Kurdish border town, despite being targeted by US-led coalition air strikes.
"There were clashes overnight. Not heavy but ISIS is going forward from the southwest. They have crossed into Kobane and control some buildings in the city there," said Rami Abdulrahman, head of the Observatory, a group that monitors the conflict with a network on the ground. ISIS is a former name for IS.
"They are about 50 meters inside the southwest of the city," Abdulrahman said.
An estimated 180,000 people have fled into Turkey from the Kobane region following the IS advance. More than 2,000 Syrian Kurds including women and children were evacuated from the town after the latest fighting, a member of the Kurdish Democratic Union Party (PYD) said on Monday.
