Rajnath Singh was told that a team of National Investigation Agency has already visited the blast site.
Home Minister Rajnath Singh Monday reviewed security situation in the country, particularly in Punjab where three people were killed and 20 others injured in a grenade blast, officials said.
Senior officials of the Home Ministry and security agencies briefed the home minister on the explosion at a religious gathering near Amritsar on Sunday, an incident which police are treating as a "terrorist act".
The home minister directed the officials to provide all assistance to the Punjab government in their investigation to arrest the perpetrators of the crime, a home ministry official said.
Mr Singh was told that a team of the National Investigation Agency has already visited the blast site along with their investigators and explosive experts.
Three persons, including a preacher, were killed and 20 others injured when two-motorcycle borne men threw grenade on a religious congregation on the outskirts of Amritsar.
The incident took place inside the Nirankari Bhavan's prayer hall at Adliwal village near Amritsar's Rajasansi, police said.
A religious congregation of the Nirankari followers was being conducted inside the Bhavan at the time of the incident.
The Sant Nirankari Mission is a spiritual organisation and the Bhavan lies close to the Amritsar international airport and the Indo-Pak border.