Security forces across the nation were on high alert after a series of bomb blasts in the temple town of Varanasi in Uttar Pradesh on Tuesday evening.
Security was beefed up at major public places, famous temples and religious institutions.
High alert was sounded in major cities including national capital New Delhi and Mumbai too.
"We are taking precautionary steps and have deployed personnel at all key public places and temples," said Delhi’s Deputy Commissioner of Police AK Singh.
Among public places, police on duty at metro stations, railway stations and bus stands were asked to be on alert.
"We have deployed over 400 police vans at major public and religious places in the capital," said Singh.
He added that district police have also been asked to keep a close vigil near Delhi’s borders and to monitor the vehicles coming into the city.
He said that all district police headquarters in the capital were asked to step up vigil in their areas and also to monitor vehicles coming into the city.
Singh added that no threat information was received and Delhi Police were only taking precautionary steps.
Three blasts in Varanasi, about 670 km from here, claimed at least four lives and injured many people.
High alert in Maharashtra A state of high alert was declared in Maharashtra, particularly in Mumbai.
Authorities swung into action taking several precautionary measures to avoid any untoward incident in the state after the Varanasi blasts.
Police officials said that the important temples in the city have particularly been put on alert with close to 20,000 police personnel on duty for the next 24 hours.
"Big and popular temples like the Siddhivinayak Temple (Prabhadevi, central Mumbai) and Swaminarayan temple (Dadar, central Mumbai) already have security covers provided by us for the past many months," said Deputy Commissioner of Police (operations) RN Tadvi.
"We have cordoned crowded places and important railway stations in the city too, which could be possible targets," Tadvi said.
"The red alert would remain for the next 24 hours and if needed we will have a high level meeting on Wednesday," Tadvi said.
Gujarat on high alert High alert has been sounded in Gujarat and security at all major temples have been beefed up. "A high alert has been sounded across Gujarat after the blasts in Varanasi and security has been beefed up at all major religious institutions including Akshardham temple, Somnath and Dwarka," Director General of Police AK Bhargava said.
"Two companies (200 personnel) of police have already been deployed at the Kalupur railway station of Ahmedabad where a powerful RDX explosion had injured several persons on February 26," he added.
The official also said that security is already tight at Akshardham temple in Gandhinagar.
"We are keeping a tight vigil over all the religious institutions in the state," he added.