International Desk: The United Nations has appealed for more than $1bn in funds for the Turkish earthquake relief operation, just two days after launching a $400m appeal for Syrians.

UN aid chief Martin Griffiths, who visited Turkey last week, said on Thursday that the people have “experienced unspeakable heartache”, adding: “We must stand with them in their darkest hour and ensure they receive the support they need.”

The February 6 earthquake has so far killed at least 36,187 in southern Turkey, while authorities in neighboring Syria have reported 5,800 deaths.

Rescue efforts have continued in Turkey, but the number of people rescued daily has dwindled significantly.

A teenage girl was pulled alive from the rubble in the province of Kahramanmaras on Thursday – more than 10 days after a devastating earthquake hit the region. But such rescues have become increasingly rare.

Read More: Turkey quake rescuers find ‘miracle’ survivors but frustration grows

The 17-year-old was safely extracted from the ruins of a collapsed apartment block, broadcaster TRT Haber reported, 248 hours since the 7.8 magnitude earthquake struck in the dead of night on February 6.

For families still waiting to retrieve their lost relatives, there is growing anger over what they see as corrupt building practices and deeply flawed urban development that resulted in thousands of homes and businesses disintegrating.

Turkey has promised to investigate anyone suspected of responsibility for the collapse of buildings and has ordered the detention of more than 100 suspects, including developers.