Chandigarh, Jan 24 (IANS) Police Sunday cordoned off Zirakpur town of Punjab's Mohali district and conducted an extensive search after two grenades were found late Saturday.

Nabha village in Zirakpur where the grenades were found is barely 1.5 km from the Indian Air Force (IAF) station. IAF officials also visited the spot to appraise themselves of the situation.

'We have cordoned off the entire area (where the grenades were found) and our special teams are searching the vicinity to gather vital clues in connection with the discovery. We could not search the area properly due to darkness yesterday (Saturday),' Derabassi Deputy Superintendent of Police J.S. Khaira told IANS.

'We also cannot deny the possibility of recovery of more grenades in the search operation. So far, we have not disposed off the grenades. We would take the help of Army personnel to ascertain their contents as we do not possess the right expertise required for this,' he said.

Zirakpur town is 10 km from state capital Chandigarh.

Meanwhile, security was also beefed up in the neighbouring Chandigarh city following the discovery of grenades.

'We have alerted our patrolling teams and personnel deployed at all checkposts to increase their vigil and to keep an eye on anti-social elements. We have made adequate security arrangements for the upcoming Republic Day celebrations,' a senior Chandigarh police officer said.

A bomb was discovered Monday outside a liquefied petroleum gas (LPG) bottling plant in Patiala district, around 50 km from Chandigarh, and was defused by the bomb disposal squad of Punjab Armed Police (PAP).

A Punjab Police official said anti-social elements might be planning to plant bombs at public places ahead of Republic Day Jan 26.

'We cannot ignore this incident. We have also got inputs from our intelligence teams that there is threat of a terrorist attack in Punjab. We are taking this chance recovery of grenades very seriously,' the official said.