Last checked at 
* Second day of technical problems for online bankingservices
* HSBC says not caused by cyber-attack or malicious activity
* UK lawmaker says to ask HSBC CEO for explanation (Adds new comment by HSBC)
By Sinead Cruise
LONDON, Jan 5 (Reuters) - HSBC said on Tuesdayonline banking was returning steadily to service after ablackout affected its customers in Britain.
Europe's biggest bank assured customers they would not "loseout", as technical problems ran into a second day. It was stillmonitoring the situation "very closely", it said.
In a statement apologising for the faults, first reported onMonday, a spokesman said: "We are currently experiencing issueswith our Online and Mobile banking. Personal Mobile banking isworking but due to high demand customers may experience delays."
Britain's retail banks have been hit by a number oftechnology failures in recent years, causing inconvenience forhundreds of thousands of customers and prompting lawmakers tocall for more investment in financial technology.
"The frequency of these failures across the financialservices sector suggests a systemic weakness in ITinfrastructure. This is concerning," Andrew Tyrie, aConservative lawmaker who also chairs parliament's TreasurySelect Committee, said in a statement.
"I will be asking the Chief Executive of HSBC, and theregulators, for an explanation of these failures, and actiontaken to sort them out. They just keep coming."
While HSBC offered no explanation for the cause of theglitch, John Hackett, HSBC's UK Chief Operating Officerconfirmed the outage was not due to a cyber-attack or any othermalicious act, such as a Distributed Denial of Service (DDOS), amechanism often used by cyber criminals trying to disruptbusinesses and companies with significant online activities.
Business customers can still access online and mobilebanking services, the bank said, but both were running atsignificantly reduced capacity following the outage.
The bank has not estimated when full service will resume butsaid its teams were working "non-stop" to restore the servicesand regular updates will be provided.
"We will ensure customers do not lose out as a result ofthis issue. Any fees customers incur as a result of this outagewill be waived," Hackett said.
HSBC has previously suffered IT problems. Last yearthousands of Britons failed to receive their wages on the Fridayprior to a long holiday weekend, when some business customerswere blocked from making payments.
State-backed Royal Bank of Scotland has promised toinvest hundreds of millions of pounds in its computer systemsafter a series of high-profile glitches.
Its last significant outage in June last year led to delaysin the processing of around 600,000 payments across its RBS,NatWest, Ulster Bank and Coutts businesses. (Reporting By Sinead Cruise; editing by Simon Jessop and RachelArmstrong)
