Mumbai, March 1 (IANS) Bollywood superstar Amitabh Bachchan's office here was attacked Friday night by unidentified people."My bungalow Janak where I've my office on the 13th Road was attacked last night. Four persons in a car threw bottles," an unfazed Bachchan told IANS Saturday.

" The details about the car, the make and the number, were given to the cops for investigation."

The office is a stone's throw away from his residence Jalsa in Juhu.

Big B was out of town when the attack took place, attending a memorial service for his friend and Samajwadi Party leader Amar Singh's father in a village in Uttar Pradesh.

The incident comes after Maharashta Navnirman Sena (MNS) leader Raj Thackeray's campaign against north Indians settled here. In his tirades, Thackeray repeatedly ridiculed Bachchan.

The actor, however, refused to comment further on the attack, which left his family further worried about the stress that was taking its toll on him.

"He has been shooting in gruelling winter conditions in Shimla and Manali for Shoojit Sircar's film. And it hasn't been easy. He had severe breathing problems. But he continued shooting ignoring all the verbal attack on him in Mumbai," said a close family source.