Las Vegas' famous "Welcome to Fabulous Las Vegas" sign has been marked on its main face and one of its structural legs with red graffiti, officials said.

Russell Davis of the Clark County Department of Public Works said authorities discovered Monday that someone had used a red Sharpie marker to deface the sign, the Las Vegas Sun reported Tuesday.

The sign, which was erected in 1959 and was entered into the National Register of Historic Places in May, is owned by the Young Electric Sign Company and is leased by Clark County.

Davis said company representatives are planning to visit the sign Tuesday to determine whether they can remove the graffiti without the help of county contractors.

A spokeswoman for the sign company said officials recently repaired vandalism damage to the sign.

"We just repaired that sign a couple weeks ago," the spokeswoman said. "A couple weeks ago, somebody threw a rock through it."