The drills were meant to assess the preparedness of the police to deal with a terror attack, the authorities say.

A video of a mock terror excercise in Gujarat's Surat district shows five policemen restraining three dummy militants wearing Muslim skullcaps and long tunics.

In another video, the security forces are shown holding two alleged terrorists at the site of Gujarat's Narmada dam. The men shout: "Take our lives if you want. Islam zindabad (long live Islam)."

Modi's silence on these issues is emboldening extremist Hindus, say critics

A number of political parties, including the Islamic organizations, condemned the "stereotyping of Muslims," who make up nearly 14 percent of the country's 1.2 billion population.

With both videos going viral on social media, the state's police and the ruling Bharatiya Janata Party (BJP), which is in power in the western state of Gujarat as well as the capital New Delhi, have come under heavy criticism.

"The mock drill was a routine police exercise conducted a week ago. If such an incident (portrayal of Muslims as terrorists) had taken place, we will conduct an inquiry and take necessary action against those responsible," Jaypalsinh Rathore, a senior police official, told DW.

The police further said the drills were carried out ahead of two high-profile events in the state: Pravasi Bharatiya Divas - to acknowledge the contribution of overseas Indians to the country's development; and the Vibrant Gujarat Investors Summit later this month, in which Prime Minister Narendra Modi and US Secretary of State John Kerry will take part.

Angry reactions

After coming under fire, Gujarat's chief minister, Anandiben Patel, admitted it was a "mistake" to show dummy terrorists in the drill as Muslims, and that it was "wrong to associate a religion with terrorism."

But the damage has already been done. Political parties have come down hard on the Hindu nationalist BJP. "It (mock drills) is similar to racial profiling, which is very bad. They (police) should apologise otherwise they should be taken to the court," Kamal Farooqui of the All India Muslim Personal Law Board told DW.

Ali Anwar, leader of the Janata Dal (United) party, also slammed the drill. "Prime Minister Modi headed the state for many years but we still see such incidents taking place (in his home state). It is very unfortunate and shows the mindset of the people. Terrorism should not be shown in relation to any religion," Anwar said.

Modi's 'silence'

Earlier this month, a group of Muslims complained they had been tricked into attending a conversion ceremony by Hindu extremists. A Hindu priest-turned-lawmaker belonging to the ruling BJP had planned a mass conversion ceremony on Christmas Day, but that was put off after the uproar in the Lok Sabha, the lower house of parliament.

The issue has become more prominent due to the fact that Modi's name has been somewhat associated with anti-secular politics. In 2002, when Modi was Gujarat's chief minister, some 1,000 people, mainly Muslims, were killed in communal riots. His opponents accused him of ordering the police not to intervene in the violence, a charge Modi and his party have repeatedly denied.

Is India's secularism under threat?

The South Asian country's main opposition party, the Congress, believes that communal politics has resurfaced in India ever since the conservative politician took power in May 2014.

"These incidents will promote terrorism. The BJP government is responsible for this," said Rashid Alvi, a Congress spokesperson.

Observers say that extremist Hindu groups are being able to push forward their anti-minority Hindu "rashtra" (nation) agenda due to the fact that PM Modi has opted to remain silent on these issues.

"The Premier must act. He has surprisingly maintained a studied silence on all these matters. If he claims that inclusiveness and development are his goals, then he must speak up against the politics of hate and work for the welfare of the minorities," Zulfikar Hakeem, a Muslim cleric, told DW.