Indian Prime Minister Narendra Modi and his Cabinet ministers briefed the senior leadership of the Hindu group Rashtriya Swayamsevak Sangh (RSS) on their government's achievements during a three-day meeting last month.

The meeting, though not the first of its kind, was the largest in scope. Cabinet ministers reportedly gave presentations and received feedback from RSS leaders, who maintained the meeting was merely to better connect with the Bharatiya Janata Party (BJP).

For many, it was a sign of the group's clout. The RSS, which describes itself as a cultural and social organisation, is the country's most powerful Hindu group and seen as the ideological mentor of the BJP.

It is affiliated with dozens of other outfits through the Sangh Parivar or family of the RSS, which represents the Hindu nationalist movement.

Scores of Hindu groups, some directly affiliated to the RSS and others working independently, operate throughout the country, where 80 per cent of the population is Hindu.

Some groups affiliated with the RSS regularly grab headlines, while others work quietly in specific areas like education, social work and trade unionism.

Among prominent groups promoting Hindu culture is the Vishva Hindu Parishad (VHP) or the World Hindu Council, the religious face of the RSS. Founded by RSS leaders in 1964, it is now in the news for issuing a decree prohibiting Muslims from entering dance programmes in the state of Gujarat.

The VHP, which warned of "dire consequences" for those who ignore the ban, claimed that it aimed to prevent a "love jihad" - Hindu women eloping with Muslim men. The VHP has many wings, including one to protect cows, and others to promote religious regeneration and Sanskrit.

The VHP's youth wing Bajrang Dal has often hit the headlines for shenanigans like disrupting Valentine's Day celebrations and harassing young couples. Last year, they threw rotten tomatoes at couples celebrating Valentine's Day in at least one city.

Other groups that have been making news include the All India Hindu Mahasabha, which is not affiliated to the RSS. The police recently filed a case against its leader Sadhvi Deva Thakur for saying that Muslims and Christians should undergo sterilisation to restrict their populations from increasing because that posed a threat to Hindus.

What worries the police and security agencies most is the rise of extremist Hindu groups.

Members of the Abhinav Bharat have been accused of being behind several blasts in recent years - including in 2008 in the town of Malegaon in the state of Maharashtra which killed several people, and in 2007 in the Pakistan-bound Samjhauta Express train which killed 68.

The Sanatan Sanstha has been in the news over the arrest of one of its members for the murder of rationalist Govind Pansare, a Communist Party of India member, who was shot dead outside his house in February this year.

The group is also believed to be connected to the killing of rationalist and author M.M. Kalburgi in August. There have been calls to ban the group.

Nirmala Ganapathy