Rebels trying to topple President Idriss Deby on Saturday attacked a town in eastern Chad where thousands of refugees are taking shelter, officials said.

There was heavy fighting for about an hour in Goz-Beida before the gunfire died down, said an aid worker in the town, who asked that his name not be used for fear of reprisals. It was not clear if there were casualties.

Chad's communications minister, Mahamat Hissene, and a spokesman for the EU peacekeeping force in the area confirmed the attack.

Click here for photos.

Eastern Chad is the temporary home to some 300,000 refugees who have fled the Darfur conflict, just across the border in Sudan. The region also has camps for 187,000 Chadians displaced by fighting both locally and in Darfur.

Chad has suffered from the spillover of Darfur's five-year-old conflict between ethnic African rebels and the Sudanese government.

The European Union is deploying 3,700 troops, including 2,200 French soldiers, to help protect Sudanese refugees and Chadians uprooted by the conflict.

The senior Irish army spokesman, Commandant Gavin Young, confirmed that an armored Irish patrol came under fire as they were monitoring a clash between the Chadian army and rebel forces. There were no Irish casualties.

He said Irish and Dutch soldiers based at Camp Ciara, the main Irish military camp near Goz-Beida, have since been providing armed escorts and refuge inside the camp for aid workers caught up in the fighting. He could not say how many aid workers had taken up the offer.

"It is not clear who fired upon our troops. Irish troops briefly returned warning fire from their armored vehicles," he said.

He said Irish troops were reporting the security situation in Goz-Beida on Saturday evening as "calm but tense."

Camp Ciara is home to 390 soldiers from Ireland's 97th Infantry Battalion and 60 Dutch Marines. Many of the troops arrived there only 12 days ago.

The French Foreign Ministry said it was "following the situation in eastern Chad with great attention."

Earlier this month, refugees and aid workers in eastern Chad told members of the U.N. Security Council that their biggest worries are insecurity and banditry, which have been on the rise in the area for months.

Rebels battled forces loyal to the president Feb. 2-3 in and around N'Djamena, the capital of the former French colony in Central Africa. The Red Cross said more than 160 people were killed and 1,000 wounded in the fighting, which reached the edge of the presidential palace before the rebels were driven out of N'Djamena and back toward Chad's eastern border.

Sudan broke diplomatic relations with Chad last month, accusing its government of backing rebels from the Darfur-based Justice and Equality Movement who attacked near the Sudanese capital. Chad in turn closed its border with Sudan and halted bilateral trade.