At least 70 people - including three children - have been killed in airstrikes over Yemen.
A further 130 people are said to have been injured in the hit on a detention centre in Yemen, Doctors Without Borders said.
It comes as the Saudi-led coalition continues to ramp up deadly offensive on rebels.
Another airstrike on Friday hit a telecommunications building in the port city of Hodeidah, causing a nationwide internet blackout.
At least three children were killed as they played football at the time of that attack alone, Save the Children said.
The Norwegian Refugee Council said the internet blackout, which was still ongoing as of Friday evening, would affect aid delivery, reports CNN.
The Saudi-led military coalition has been fighting the Iran-aligned Houthi group in Yemen since 2015.
The coalition said the report of dozens of deaths on Friday would be investigated "using an internationally approved, independent process."
Tens of thousands of civilians, including more than 10,000 children, have been killed or wounded as a direct result of the fighting.
Millions have been displaced and much of the population stands on the brink of famine.
The conflict has its roots in the failure of a political process supposed to bring stability to Yemen following an uprising in 2011.
Long-time authoritarian president, Ali Abdullah Saleh, eventually handed power to his deputy, Abdrabbuh Mansour Hadi who struggled to deal with growing unrest.
The Houthi movement took advantage of the new President's weakness.
Many ordinary Yemenis - including Sunnis - supported them, and in late 2014 and early 2015 the rebels gradually took over the capital, Sanaa.
