A Chinese construction firm operating in the restive southern Philippines was attacked by a mortar attack, and a heavy equipment of the company was destroyed, but no one got injured in the incident, local police said Friday.

Elias Dandan, the police chief of Pikit, a municipality in the southern province of North Cotabato, said a construction site of China International Water and Electric Corporation which was repairing a national road in the area was attacked by mortar around 9:00 p.m. Thursday, no one was hurt in the blast, but a backhoe of the company was destroyed.

According to Dandan, the perpetrators used a homemade 81 millimeter mortar shell to mount the attack.

"The attack was carried out by an extortion group linked to Muslim rebels," he said.

The incident was the second attack against the Chinese firm.

On March 2, two Filipino workers of China International Water and Electric Corporation were hurt in a bomb blast along the highway in the township of Pigcawayan .

No group has claimed responsibility for those attacks.