New Orleans police came up empty Saturday in their search for a gunman who entered a Gentilly Wal-Mart store about 6 a.m., causing customers and employees to flee and a SWAT team to descend on the scene.

The store was closed and Chef Menteur Highway was blocked off in both directions for several hours as officers with guns drawn searched the store and its parking lot for a man who witnesses said was wearing a hooded shirt and a covering over his face.

Police said no shots were fired, and no one was injured. It was not clear whether the gunman intended to rob the store.

The Wal-Mart reopened later in the day after employees were questioned.

The Gentilly Wal-Mart employs about 300 people, said Clint Sampson, who manages another Wal-Mart store and was called to the scene to assist the Gentilly store with reopening. Sampson did not know how many people were working Saturday morning.

Robert Silva had gone into the store to buy water before heading to his work shift in the French Quarter. As he stood at the checkout counter about 6:10 a.m., he said, he “noticed in my peripheral vision to the right there was a man in a hoodie.”

“I saw something in his hand,” Silva said. “I didn’t pay too much attention, but the ladies who work there came from around the corner and said there was a man with a gun. That’s when the manager said, ‘Everybody stay calm and walk out of the store.’ ”

Silva said he and others walked out and began dialing 911.

By the time police arrived on the scene, most of the people inside the store already had fled through the main entrance and a back door, Silva said.

Police said the man entered through the front entrance, then turned toward the customer service desk before running through the deli section. He then entered a storage area and left through a fire exit. He was last seen running east toward Louisa Street.

Last month, a man wearing a Wal-Mart uniform robbed the same store of a reported $120,000 in cash. The man fled in a waiting car. He is still at large.