The online security company Trend Micro reported Friday that cyber hackers tried to infiltrate the email services of Microsoft (Hotmail) and Yahoo !.

ioThe complaint was made at a time when a federal investigation into cyber-espionage, discovered by Google, is running against Gmail (Google) hot mail accounts.

"Although everything points to the fact that these two cyber attacks were conducted separately, there are several similarities," said Nart Villeneuve, Trend Micro cyber attack specialist.

Last Wednesday, Google denounced a hacking campaign directed from China to Gmail accounts of US officials, journalists and Chinese dissidents.

In addition to monitoring the content of these users' emails, it is likely that hackers have polled the computers to determine the type of software used.

"By knowing the type of software installed on a computer, including the antivirus program, (cyber hackers) can attack any vulnerable software accurately," said Villeneuve.

"These types of attacks are very likely to succeed," Villeneuve concluded.