Three young sisters - two of them toddlers - were killed while their mother and a neighbour critically injured as a swarm of hornets attacked them near their house on Saturday in Birganj upazila of the district.

Nine-month-old Meem, Farzana Begum, 3, and Hadisa Begum, 8, were daughters ofTanjila Begum and Islam Mia of Arji Laskara village in the same upazila.

The three siblings, their mother and the neighbour, Rahima Khatun, 50, were stung by the hornets after a hornet's nest fell off a bamboo cluster near their house due to a strong wind on Saturday afternoon, said Ramzan

Ali, a resident of the village.

Locals came to their rescue and rushed all the victims to Thakurgaon Modern Hospital where Farzana and Hadisa — a 1st grader at Arji Laskara Government Primary School - succumbed to their injuries the same night.

The youngest of the victims, Meem, and the children's mother, Tanjila Begum, 36, were transferred to Rangpur Medical College Hospital (RMCH) as their condition was deteriorating, said Dr. Shukumar Roy of Thakurgaon Modern Hospital.

Meem died yesterday at RMCH while her mother is still there in a critical condition, Zahangir Hossain, officer-in-charge of Birganj Police Station, said.