Around 40,000 people have fled their homes in Chad in the past two weeks following attacks by militant group Boko Haram, according to an aid agency, as the insurgency stokes an escalating humanitarian crisis in the region around Lake Chad, Voice of America reported Saturday.

Médecins Sans Frontières (MSF) said many of the displaced people have gathered in makeshift camps where its staff were treating patients with diarrhea, malaria and respiratory infections, as well as malnourished children.

"Some pregnant women have walked several kilometers in searing heat to seek medical attention," said Federica Alberti, MSF's head of mission in Chad. "People are living without proper shelter, and do not have access to food or clean drinking water."

The Lake Chad region has become increasingly unstable since 2013, with Boko Haram violence triggering a growing crisis. At least 1,300 people have died in fighting so far this year in the region, MSF said.