Ctrip, a leading online travel agency in China, has said that an employee's error had led to the recent breakdown of its services.
The company told Sina.com.cn that the breakdown was caused after an employee accidentally deleted critical lines of code from its production server. But Ctrip didn't provide further details.
Ctrip claimed that its systems had been upgraded to prevent such accidents from happening again.
Both the Ctrip website and app are used to make hotel and flight bookings. Since Thursday morning (May 28, 2015), users found that they couldn't access Ctrip's website and mobile app services.
Ctrip soon posted a message on its website, suggesting that users could visit eLong.com for booking services.
Ctrip acquired a 37.6 percent stake in eLong last week, becoming the largest single shareholder of its former rival.
Strangely, as Ctrip diverted its traffic to eLong, the latter soon reported possible distributed denial-of-service attacks.
It took Ctrip engineers about 12 hours to get its services back online. However, rumors have already surfaced that Ctrip's servers were brought down by hackers.
While Ctrip didn't comment on the hacking rumors, it has reassured users that its database, which contains users' credit card information, remains intact.
The company is listed on the NASDAQ stock market. Its shares fell about 1.6 percent on Thursday following the hacking rumors.