Four more energy suppliers have gone bust as a result of soaring gas prices, the industry's regulator has announced.
Ofgem said on Tuesday that Omni Energy, MA Energy, Zebra Power and Ampoweruk had all ceased trading, meaning a new supplier will be sought for around 23,700 customers.
The latest collapses came a day after Bluegreen Energy Services, which had 5,900 customers, went out of business on Monday.
Over the last two months, 18 companies have gone bust after a surge in global gas prices has caused losses for suppliers who are unable to pass on all of the costs to customers.
In a statement, Ofgem sought to reassure customers that their credit balances will be protected and transferred to a new supplier.
The regulator said it will choose a new supplier for affected customers, which will then contact them, and assured that energy supply and funds paid into accounts will be protected.
Zebra Power supplies about 14,800 domestic customers while Omni Energy supplies about 6,000 pre-payment domestic customers, MA Energy supplies about 300 business customers and Ampoweruk supplies about 600 domestic customers and 2,000 businesses.
Neil Lawrence, director of retail at Ofgem, said: "We know this is a worrying time for many people and news of a supplier going out of business can be unsettling.
"I want to reassure affected customers that they do not need to worry: under our safety net we'll make sure your energy supplies continue.
"If you have credit on your account the funds you have paid in are protected and you will not lose the money that is owed to you.
"Ofgem will choose a new supplier for you and while we are doing this our advice is to wait until we appoint a new supplier and do not switch in the meantime.
"You can rely on your energy supply as normal. We will update you when we have chosen a new supplier, who will then get in touch about your tariff."