Authorities investigating suspected arson at Beyoncé’s and Jay Z's mansion

A Tuesday fire at a New Orleans mansion belonging to Beyoncé and Jay-Z is now under investigation as "simple arson."

An eyewitness tells ABC affiliate WGNO that "a man was seen running from the home and that the fire."

The New Orleans Fire Department didn't reveal the extent of damage, but reported that 22 firefighters battled the blaze for more than an hour.

Neighbors said the home has been vacant for years and has become run down, though Beyoncé and Jay-Z have a “great gardener who takes care of the boxwoods.”

The three-story property was built in 1926 and was initially a church, WGNO reports.