Expressing distress at the killing of a Sikh sect leader in Vienna, government on Monday said it was in touch with Austrian authorities to ensure that those guilty of violence in the gurdwara there were brought to book and asked the people of Punjab to exercise restraint.

While appealing to the people for calm and restraint, Prime Minister Manmohan Singh said he was "deeply distressed over the outbreak of violence in Punjab after the Vienna incident. Whatever the provocation, it is important to maintain peace and harmony among different sections of the people."

Invoking the preachings of the Sikh Gurus, Singh said "in areas where curfew has been imposed, it is necessary that people should go back to their homes and allow the security forces to restore law and order."

Soon after assuming charge, External Affairs Minister S M Krishna said the government was in touch with Austrian authorities and closely monitoring the situation.

The government, he said, was "determined to ensure that the perpetrators of this completely mindless and wanton act are brought to justice."

"Two groups of people owing allegiance to different families have set up confrontation amongst themselves and let the gurdwara to be made the place where attacks and counter attacks have taken place," Krishna said.

Sant Ramanand, a Dera head who was visiting Vienna, was killed and 30 others were also injured in the clash on Sunday.

Punjab Chief Minister Parkash Singh Badal also appealed for calm and asked people not to be provoked by elements spreading unrest.