DHAKA (Reuters) - Muslim-majority Bangladesh has ordered telecom operators to shut down services along the border with India, citing security concerns over Indian Prime Minister Narendra Modi’s new citizenship law which critics say discriminates against Muslims.

Mobile network coverage has been suspended for a one-kilometer-wide band along the border with India until further notice “for the sake of the country’s security in the current circumstances”, officials said in a statement released late on Monday.

The move stems from concerns that Indian Muslims might seek to flee to Bangladesh, two officials told Reuters. They spoke on condition of anonymity because they were not authorized to publicly discuss the measure.

The Indian law gives citizenship rights to Hindus, Sikhs, Christians, Jains, Buddhists and Parsis from Bangladesh, Afghanistan and Pakistan who settled in India before 2015 - but not to Muslims.

Critics fear it is a prelude to a broader National Register of Citizens in which residents would be asked to prove their citizenship, which activists say could put poor Muslim families lacking documentation at a disadvantage.

India’s foreign ministry did not immediately respond to a request for comment on Bangladesh’s move.

The two countries share a fertile border of more than 4,000 km (2,500 miles). Millions of Bangladeshis live alongside the frontier, mainly engaged in cross-border trade of medicines, agricultural commodities, milk and livestock.

“The decision to suspend mobile services could impact about 10 million people living on the border,” said a senior official at a mobile phone company in Dhaka.

Indian news website ThePrint on Monday reported that Bangladesh Prime Minister Sheikh Hasina had sought a written assurance from the Hindu-nationalist Modi government that it would not expel illegal immigrants across the border.

Hasina’s office was not immediately available to comment on the news report.

Earlier this month, Bangladesh’s Foreign Ministry said one senior diplomat was attacked during a protest in India’s northeastern state of Assam, which shares a border with Bangladesh and has the highest incidence of illegal immigration from its neighbor.