Online trading platform Plus500 Ltd said on Monday that it lost more than half of its quarterly revenue to customers generating unusually strong trading results, sending its shares down more than 10%.

The company, which kept its annual outlook unchanged, said its second-quarter revenue surged to $249 million, but the trading gains reduced that figure to about $102.5 million.

Unlike many of its peers who act as go-betweens for customers to make bets on financial markets against other institutions and traders, Plus500 makes markets for its customers. This means if the customers bet correctly more than incorrectly, it can lose money.

Over time, it expects the trading results to have a neutral effect on its business, Plus500 said, while declining to specify which asset classes or traders were involved in the losses.

However, it said the bulk had come in the week ended June 5, when stock and oil markets globally were rallying strongly.

The company, one of the easy access mobile trading platforms which allow customers to make leveraged bets on financial markets from oil to currencies, has added 100,000 new customers in the second quarter.

As bankers and brokers work from home, the Financial Conduct Authority had warned that remote working may raise new risks around handling sensitive information and so financial firms must check if their surveillance systems can spot suspicious activity.

Shares of the FTSE 250-listed firm, which have gained more than 25% so far this year, were down at 1,087 pence in morning trade.

(Reporting by Yadarisa Shabong in Bengaluru; Editing by Patrick Graham and Arun Koyyur)