N'DJAMENA - Three suicide bombers attacked the island of Koulfoua on the Chadian side of Lake Chad on Saturday, killing around 30 people and injuring 80, two security sources told Reuters.

The sources said the attacks coincided with market day.

Earlier this year, thousands of people fleeing Islamist militant group Boko Haram sought refuge on the island although it was not immediately clear if they were still based there.