The U.S. Secret Service says it is investigating the hacking of Fox News' political Twitter account and posting false messages reporting the assassination of President Barack Obama.

The Secret Service, which has the job of protecting U.S. presidents, says it will do an “appropriate follow-up” to the matter.

Hackers broke into the Fox Twitter feed Monday and posted six messages saying Mr. Obama had been shot dead.

Fox News released a statement Monday saying the reports were “false” and “malicious,” and apologized for any distress they caused. The Twitter feed was suspended after the hacking became apparent. Fox says it has asked the Twitter company for an investigation.

The tweets began in the early-morning hours of Monday, reporting that President Obama had been shot twice while campaigning at a restaurant in the state of Iowa. The U.S. broadcast network later confirmed that Mr. Obama spent the U.S. Independence Day holiday in Washington, as scheduled.

The anonymous hacking group called Script Kiddies is claiming responsibility for the cyber attack.