The death toll of the two back-to-back explosions outside Kabul airport has increased to over 100 killed and 150 wounded.

US officials confirmed that among those killed were 13 American soldiers. Taliban sources said the total death toll was over 100.

Turkish officials also have confirmed that several of its soldiers were wounded in these explosions.

Eyewitnesses say that explosions occurred amid thousands of people gathered outside the airport trying to leave the country.

Taliban spokesman Zabihullah Mujahid said that the explosions happened in areas controlled by the American soldiers.

The blasts occurred from inside a crowd of Afghans close to the Abbey gate area who were trying to leave the country, said the US Pentagon's press secretary John Kirby.

"We can confirm that the explosion at the Abbey Gate was the result of a complex attack that resulted in a number of US and civilian casualties. We can also confirm at least one other explosion at or near the Baron Hotel, a short distance from Abbey Gate. We will continue to update,” Kirby said.

At least 52 people were wounded in the blast near the Baron Hotel, a short distance from Abbey Gate in Kabul airport, said Zabihullah Mujahid, a spokesman for the Taliban, adding that two explosions occurred in the area and the other blast also has casualties but the number is not yet clear.

Two US officials said at least one of the explosions appeared to be from a suicide bombing, according to a Reuters report.

A Taliban official told Reuters that at least 13 people were killed in the blast, including children, and many Taliban guards were wounded.

A US official told Reuters as many as three US service members were among those hurt, and that US casualty numbers were expected to increase, according to initial information.

At least one of the US personnel was seriously hurt, an official said.

Reuters also mentioned that US President Joe Biden has been briefed on the explosion, according to a White House official.

Biden was in a meeting with security officials about the situation in Afghanistan.

Abdullah Hamim, a TOLOnews reporter at Emergency Hospital, said that several people who were wounded in the blast have been taken to the hospital.

No group has claimed responsibility for the blast.

Previously the US embassy in Kabul warned US citizens to avoid the airport due to a possible Daesh attack.