Indian Prime Minister Narendra Modi has said those responsible for an explosion i Delhi that killed at least eight people “will not be spared”.

On Monday evening a car exploded near the Red Fort, one of the Indian capital’s most visited historic sites. Several others were also injured in the blast.

In his first public remarks since the explosion on Tuesday, Modi said he was in touch with agencies investigating and said they will “get to the bottom of this conspiracy.”

India’s federal investigative agency – the NIA – has taken over the case under anti-terror laws. The police has not disclosed the reason for doing so.

India’s Home Minister Amit Shah chaired a high-level security review meeting with senior officials on Tuesday, but no details have emerged on what was discussed.

Shah, along with other agencies, said they were investigating the cause of the explosion and “exploring all possibilities”.

He posted on X that he had instructed officials “to hunt down each and every culprit behind this incident”.

Following the blast, police said at least six bodies had been identified so far.

Sonu Agrawal said his older brother, Lokesh, was killed in Monday’s blast while on his way back from visiting a relative at a hospital in Delhi.

Lokesh, father of two sons and a daughter, owned a shop in Amroha city in the neighbouring Uttar Pradesh state, his brother told news agency ANI.

“He had gone to Delhi to meet his son’s mother-in-law, who is in hospital there. Afterwards, he was near the Red Fort metro station when the blast took place,” Mr Agrawal said.

Leaders of Sri Lanka, the Maldives and Nepal are among the countries who have extended their condolences to India following the blast.

Mumbai, India’s financial capital, has been put on high alert, as has Uttar Pradesh state, which borders Delhi.

The blast happened near a metro station close to the Red Fort.

Delhi Police Commissioner Satish Golcha said the blast happened when a slow-moving car stopped at a traffic signal before it exploded.

The Fort is now closed for three days as the investigation proceeds.