NEW DELHI: Security has been tightened in the national capital following Sunday night's explosion at a cinema hall in Ludhiana which claimed six lives.
 
The capital is already on a general alert after Thursday's blast at the sufi shrine of Khwaja Mohiuddin Chisti in Ajmer.
 
"We are cautious but not panicked. We have alerted our personnel," a senior police official said, adding they were taking all steps to tighten vigil in the capital.
 
A close watch is being maintained at public places, especially cinema halls, theatres and religious places following the two blasts, the official said adding, police forces have been alerted to keep vigil at the borders.
 
Checking at inter-state bus stands, metro stations and railway stations have also been intensified, he said.
 
The city Police Commissioner had earlier asked the personnel to be more alert and requested the public to inform police about any suspicious activity or people.