Nearly 400 employees at Flybmi have lost their jobs following the collapse of the regional British airline at the weekend.

Flybmi formally appointed the restructuring firm BDO as administrators on Monday after ceasing to trade on Saturday. BDO announced that 376 employees in the UK, Germany, Sweden and Belgium have been made redundant, although some will assist with the administration.

The airline’s immediate owner, British Midland Regional, operated 17 regional jet aircraft on routes to 25 European cities but cancelled hundreds of flights at short notice over the weekend, leaving passengers stranded.

Thousands of passengers have been left out of pocket after the collapse of the airline, which operated more than 600 flights a week from regional airports including Bristol, Newcastle, Aberdeen and east Midlands.

Tony Nygate, BDO business restructuring partner and joint administrator, said: “As joint administrators, we are taking all necessary steps to ensure customers, staff and suppliers are supported through the administration process. Our job is to maximise recoveries and minimise distress for all parties, acting as smoothly and swiftly as possible.

“Customers can find information on the flybmi website regarding the steps they need to take to apply for a refund from their payment provider or travel company. We are also working with the company’s employees to provide them with guidance on how to make a claim for monies which may be due to them. In addition, we are contacting suppliers to explain how to apply for monies owed to them.”

Administrators will now evaluate Flybmi’s assets, including its former headquarters at Castle Donington, to work out how much it can return to creditors, including suppliers of fuel and food. It is thought to be highly unlikely that people who bought tickets for cancelled flights, who rank as unsecured creditors, will recover any money.

Some passengers are able to rebook via partner airlines Lufthansa, Brussels Airlines, Turkish Airlines, Loganair, Air France and Air Dolomiti, which have “shared ticket” flights with Flybmi. Ryanair and easyJet are also offering cheap rescue flights on some routes.

The group’s ultimate parent company, Airline Investments, which is owned by brothers Stephen and Peter Bond, is continuing to trade, as is its sister firm, Loganair, which has said it will step in and take over five of Flybmi’s routes from next month.

Loganair, which is headquartered in Glasgow and operates routes including around the Scottish Highlands and Islands, said it was in a strong financial position and would be flying from Aberdeen to Bristol, Oslo and Esbjerg, as well as from Newcastle to Brussels and to Stavanger in Norway. It was also “evaluating Flybmi’s wider network”.

The collapse of Flybmi threatened the continued operation of flights between Derry, in Northern Ireland, and London’s Stansted airport. Before Flybmi’s collapse the transport secretary, Chris Grayling, said the government would continue to subsidise the route, which is seen as economically important for Derry, until 2021.

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The operator of City of Derry airport said on Monday a number of airlines, including Loganair, had expressed interest in running the route.

Flybmi is the latest of a series of European airlines to struggle in recent months. Fellow British regional carrier Flybe was taken over in a cut-price deal led by Virgin Atlantic in January, while low-cost carrier Norwegian launched an emergency £270m fundraising at the end of the month when a possible takeover by British Airways owner International Airlines Group fell through.

The airline said its trading and future prospects had been “seriously affected by the uncertainty created by the Brexit process”. Rising fuel prices and increasing carbon costs resulting from the EU’s recent decision to exclude UK airlines from full participation in the emissions trading scheme had also contributed to the demise of the company.