At least 27 people have lost their lives and millions of homes are underwater following devastating monsoon floods in northeastern India and Bangladesh.

Both countries have sought military assistance to cope with the severe flooding, which authorities fear could worsen due to additional rainfall expected over the weekend.

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In Bangladesh, lightning strikes have claimed 15 lives since Friday, with four more fatalities reported from landslides, according to police officials.

The flooding in Bangladesh, possibly the worst since 2004 according to government experts, has been aggravated by runoff from heavy rains in the Indian mountains.

In Assam state, India, floods have resulted in at least nine deaths and affected two million people whose homes are now submerged in floodwaters, according to the state disaster management agency.

The Brahmaputra river, a major river in Asia, breached its mud embankments, causing flooding in 3,000 villages and agricultural lands across 28 of Assam’s 33 districts.

Sanjay O’Neil, an official at the meteorological station in Gauhati, Assam’s capital, described the rainfall as unprecedented in volume. He warned of continued moderate to heavy rainfall in various parts of Assam until Sunday.