Siddique Kappan, arrested on Monday, is a contributor for a popular Kerala-based website.
A journalist from Kerala and three others, who were arrested by the Uttar Pradesh police while on way to Hathras earlier this week, have been charged under the stringent anti-terror law UAPA, and sedition by the Uttar Pradesh police. In the FIR, the police have applied the Section 17 of the UAPA, which deals with "raising funds for a terrorist act".
Journalist Siddique Kappan was going to Hathras on Monday to cover the situation following the alleged gang rape and death of the 20-year-old woman from Scheduled Castes, which has triggered outrage across the country.
Mr Kappan, a contributor for a popular Kerala-based website, is also the secretary of the Delhi unit of Kerala Union of Working Journalists.
In a statement on Tuesday, the police said they had received information that some "suspicious people" were on their way to Hathras from Delhi. Following the tip-off, the men - Siddique Kappan, Atiq-ur Rehman, Masood Ahmed and Alam - were stopped at a toll gate in Mathura and later arrested.
Their mobile phones, a laptop and some literature they carried, were seized, the statement said.
The police claimed that the men, during questioning, revealed they had links with the PFI and its associate organisation Campus Front of India (CFI). The FIR said a pamphlet titled "I am not India's daughter" was recovered from them.
The police handling of the Hathras woman's case -- the alleged laxity followed by whisking off the body from the Delhi hospital and the subsequent 2 am cremation, keeping her family locked up, has drawn condemnation from the opposition and the civil society. Their treatment of journalists and political leaders who had tried to visit Hathras, has drawn criticism as well.
Leaders of several political parties – including the Congress and the Samajwadi Party – have been detained. Batons were used on protesting workers of the Rashtriya Lok Dal. Among the detained leaders were Congress's Rahul Gandhi and Priyanka Gandhi Vadra who had a face-off with the police last week when they were on way to Hathras to visit the woman's family.