Story highlights Unofficial "X" marking JFK assassination spot removed

City spokesman says that the work was done to "level out the streets"

A man who sells publications about the killing says he first painted the "X" years ago

The "X" marking the approximate spot in Dallas' Dealey Plaza where President John F. Kennedy was assassinated 50 years ago is no more.

The mark disappeared amid road work this week in advance of the 50th anniversary of Kennedy's death.

The city hasn't directly addressed the disappearance of the unofficial marker.

In a statement, city spokesman Frank Librio said only that the work was done to "level out the streets and remove any trip hazards."

"With thousands visiting the area this week, we think that is prudent," he said.

The X had been a popular photo spot, despite its location in a busy traffic lane.

Robert Groden, an author and Kennedy assassination conspiracy theorist who sells his publications in the plaza, told CNN last week that he first painted the X years ago.