At the mean time the official site of the Bitstamp is showing the warning message for its customer's with the title Maintenance. On the warning statement Bitstamp warned its users not to submit Bitcoins in the previous issued address.
"We have temporarily suspended Bitstamp services. As an additional security measure, we suspended our systems while we fully investigate the incident and actively engage with law enforcement officials" - Bitstamp wrote on statement.Company have assured its users that a small fraction of Bitstamp's total bitcoin reserves were affected on this breach, and the overwhelming majority of which are held in secure offline cold storage systems. Bitstamp has also said that all customers’ "balances held prior to our temporary suspension of services will not be affected and will be honored in full."
This is not the first time that hackers have targeted Bitcoin Exchange site. As earlier one of the popular Bitcoin Stock Exchange MtGox have also been hacked and hackers had stolen 750,000 BTC, which makes the company insolvent. Additionally deep-web site SlikRoad 2 have also suffered from the lose of $2 million bitcoins following a hack.
Till yet there is no evidence regarding the Bitstamp's hack, but company have assured that they had reserve its users bitcoin in a safe Cold offline storage, and soon Bitstamp service will be back on a new and safe environment.