July 20 (Reuters) - Hackers linked to Beijing accessed the email account of the U.S. ambassador to China, Nicholas Burns, in an attack that is believed to have compromised at least hundreds of thousands of individual U.S. government emails, Wall Street Journal reported on Thursday. Daniel Kritenbrink, the assistant secretary of state for East Asia, was also hacked in the cyber-espionage attack, the report said citing people familiar with the matter. Reporting by Shubhendu Deshmukh in Bengaluru Our Standards: The Thomson Reuters Trust Principles.