Expressing concern over the situation in Punjab following clashes between members of Dera Sacha Sauda sect and Sikhs, Prime Minister Manmohan Singh on Friday appealed to the people in the state and neighbouring Haryana to maintain calm.

"I have spoken to the chief ministers of both the states in the last two days. I sincerely hope nothing will be done to flare up tempers and the situation in Punjab will be brought under control," Singh told reporters on sidelines of a function at the Rashtrapati Bhavan.

He said the people should maintain calm and not allow the situation go out of control.

Immediately after the swearing-in ceremony of DMK MP Radhika Selvi as Minister of State, Union Home Secretary Madhukar Gupta rushed to the prime minister and briefed him about the situation in Punjab.

Gupta, who chaired a series of meetings last evening, had ordered rushing in of central para-military forces to Sirsa in Haryana and Punjab.

Home Minister Shivraj Patil, who also spoke to the chief ministers of both the states, told reporters that 42 companies of central forces comprising CRPF, RAF and BSF have been dispatched to Punjab and 10 companies to Haryana.

Seeking to address the issue "politically", the home minister said the Centre was keeping a close watch and had also sent an advisory to neighbouring states like Rajasthan, Delhi and Himachal Pradesh.

Punjab has been witnessing tension following clashes between supporters of Dera Sacha Sauda and Sikhs in which one persons was killed.