By REUTERS

Published: Jul 31, 2010 00:08 Updated: Jul 31, 2010 00:13

ASHKELON, Israel: Palestinians in Gaza fired a rocket into Ashkelon on Israel's Mediterranean coast on Friday, blowing out the windows of an apartment block and damaging parked cars in a residential area of the city.

No one was injured in the blast, but the attack ended over a year of calm for the city closest to the enclave ruled by Hamas and it was likely to trigger a military response by Israel.

A police spokesman said the rocket was a 122mm Chinese-made Grad, with a heavier payload and greater range than the crude, homemade rockets Gaza fighters had been launching daily until Israel's three-week military offensive into Gaza 18 months ago.

"As you see, hundreds of people live here. It's just luck that no one was killed," said Ashkelon Mayor Benny Vaknin.

Ashkelon, with a population of 125,000, lies on the coast about 12 km north of the Gaza Strip. The mayor said it was the most serious attack on the city since Israel ended its offensive in January 2009.

"Israel takes the firing on Ashkelon very seriously," Israeli Prime Minister Benjamin Netanyahu said in a statement.

The Foreign Ministry said Israel had the right to respond "at a time and in a way it deems proper."

Israel would also lodge a protest with the United Nations for an attack targeting civilians in violation of international law, it said.

UN Special Coordinator Robert Serry said in a statement "indiscriminate rocket fire against civilians is completely unacceptable and constitutes a terrorist attack."

Hamas must not allow militant violence to undermine progress in the talks between Israel and the Palestinians, he said.

No group in Gaza claimed responsibility for Friday's attack.

Hamas has said it is trying to stop fighters from firing at Israel, but smaller groups have continued to launch rockets.

On Thursday, Arab League foreign ministers meeting in Cairo gave Abbas the green light to engage in direct peace talks with Israel when he feels the time is right. ¬