Kolkata: West Bengal’s ruling Trinamool Congress on Sunday observed a ‘Black Day’ in the city and its suburbs to protest against the detention of their party leaders and MPs at the Silchar airport in Assam.

A Trinamool delegation comprising six MPs, an MLA and a state minister went to Assam on Thursday to study the situation after the draft of National Register of Citizens (NRC) was released but was detained and allegedly manhandled by the police.

Condemning the incident, several Trinamool Congress activists marched on the streets in Kolkata and Howrah wearing black badges and carrying black flags.

Roads were blocked in parts of Howrah and Rajarhat for nearly an hour on Sunday morning.

The agitators also created a rail blockade in South 24 Parganas district’s Garia railway station for nearly one and a half hours.

The Trinamool Congress and Chief Minister Mamata Banerjee have been extremely critical of the draft NRC in Assam that left out more than four million people from the list and termed it as a BJP political strategy to drive out “real Indians” from the country.

An eight-member delegation of the party reached Assam on Thursday morning, reportedly to talk to those left out of the draft NRC.

Some members of the delegation including women alleged that they were beaten up and confined in a separate room by the police.

The Trinamool leaders were arrested later that day and released on Friday.