KARACHI, Sept 2: Police were placed on high alert on Thursday night for an indefinite period in view of the 9/11 anniversary and a defence exhibition beginning here on Sept 14.

Well-placed sources said that police had received 'credible information' about plans for terrorist assaults on September 11 on the third anniversary of the attack on World Trade Centre in New York.

Police were also apprehensive of attempts of sabotage the defence exhibition in the city, the sources added. However, city police chief Tariq Jamil did not speak about any threat and said: "This is our routine exercise which we carry out at intervals," and added that the police had been put on high alert in view of the forthcoming events.

He said that the leave of police officials were cancelled, and the total force would be utilized for deployment and full mobilization to ensure a better visibility of the police in the city. Besides regular police, the officials in training centres would also be deployed on security duty.

Mr Jamil said that snap-checkings would be increased and an exercise to close and open some important roads with intervals would also be carried out. He said that the mobility of police would be increased in some areas suspected to have hideouts of terrorists.

Searches and snap-checkings in those areas would be intensified and raids on specific and general information would be conducted in these areas which he did not name. He said that coordination between police, Rangers and intelligence agencies would be improved to ensure security in the city.

Security at foreign franchise restaurants and other installations has also been beefed up. The deployment at public places, government offices and important buildings had also been increased to avert any untoward incident.