Buses carrying some 200 evacuees due to leave Kabul on a Dutch plane Thursday night were turned back hours before two attacks on Kabul airport because of the escalating security threat.

The evacuees were contacted by Dutch diplomats to tell them their flight had been cancelled because of the risk of terrorism, sources told broadcaster NOS. Hours later a suicide attack and a shooting at the airport claimed the lives of hundreds of people, including civilians, American military personnel and Taliban fighters.

The whereabouts and circumstances of most of the group are unknown, although it is believed many are still in contact with the diplomatic service.

Earlier three buses carrying 118 passengers bound for a flight to the Netherlands did manage to enter the airport safe zone after having spent over 24 hours outside the gates.

The threats put a stop the Dutch evacuation effort on Thursday with the penultimate flight from Afghanistan arriving at Schiphol airport on Friday morning with 100 people on board, 98 of whom had Dutch passports.

The Netherlands has airlifted some 2,500 people to safety since the Taliban takeover. For some 1,600  the Netherlands was their final destination.

The group comprised 300 interpreters and their families, and 211 embassy staff. EU and United Nations staff, human rights campaigners and local peole working for Dutch NGOs and media were also among the passengers.

Some 8,500 people reportedly put in a request at the Dutch embassy to be put on the Dutch evacuation list after the Netherlands relaxed the rules to include not only interpreters and their families but journalists, fixers and people who worked with Dutch troops.

It is not yet known how many will be eligible for evacuation to the Netherlands.

The fate of those who have been left behind is unclear as most rescue operations will be wound down next week. Among them are some 30 interpreters who had been on the list since August 15, caretaker defence minister Ank Bijleveld told journalists on Friday.

The Dutch still have a plane and a small military presence in the region, thought to be stationed in a neighbouring country,  in case evacuations become possible again.

In a press conference on Thursday Dutch prime minister Mark Rutte said the government has ‘a sacred duty’ to get out as many people as possible and that talks with to that end with European allies and neighbouring countries, such as Qatar and Pakistan, were ongoing.