Two months before he killed 58 people at a country music concert in Las Vegas, Stephen Paddock booked two rooms at a Michigan Avenue hotel overlooking Grant Park during Lollapalooza.

But the Nevada retiree never showed up to claim the rooms at The Blackstone Hotel across the street from the jampacked downtown music festival, which attracted about 100,000 guests each day, including Malia and Sasha Obama, and Mayor Rahm Emanuel.

Raising the eerie notion that Paddock could have carried out his horrifying slaughter in Chicago, a source with direct knowledge of the matter said on Thursday that the gunman specifically requested rooms with a view of Grant Park during Lollapalooza.

A Las Vegas law enforcement official confirmed Paddock’s Chicago reservation, saying there was no evidence the gunman ever came to Chicago that weekend.

“We can confirm there was no guest under that name who stayed at our hotel in August during the Lollapalooza Music Festival,” a Blackstone Hotel spokeswoman said. “We are cooperating with authorities on the matter.”

Chicago Police spokesman Anthony Guglielmi said the department was “in communication with our federal partners” about Thursday’s revelation.

“As you saw earlier this week the city conducts extensive public safety planning and training around major events, in close coordination with our law enforcement partners, to ensure public safety,” Guglielmi said.

With investigators probing Paddock’s whereabouts in the months before the Las Vegas massacre, authorities revealed on Thursday that, in addition to Chicago, Paddock had scouted hotels around Fenway Park in Boston.

Paddock also rented a room at the Ogden Las Vegas hotel during the “Life is Beautiful” music festival from Sept. 22-24, the weekend before the mass shooting. Chicago hip-hop superstar Chance the Rapper was among the headliners of that festival, along with Muse, Lorde and Blink-182.

“Was he doing pre-surveillance? We don’t know yet,” said Las Vegas Sheriff Joseph Lombardo. “This is all pre-conjecture.”

On Sunday, Paddock opened fire from the 32nd floor of the Mandalay Bay Hotel and Casino, killing 58 people and injuring nearly 530 at a country music festival before killing himself.

Former Secret Service Agent Arnette Heintze said the Las Vegas massacre and Paddock’s apparent interest in Chicago are likely to heighten the level of security for next year’s music festival, particularly as it relates to “threats that potentially come from high-rise properties around” Grant Park.

Potential measures include: meeting with building owners to talk about battening down the hatches and better screening guests; putting up “significant banners” or other obstructions to block the “view or vantage point” of the crowd from nearby high-rises; and positioning sharpshooters on surrounding rooftops.

“Where you typically hear counter-sniper coverage is with protecting our nation’s leaders. Sometimes, you might hear counter-snipers for big events, such as significant parades where elected officials might participate. Every inauguration there are significant teams of counter-snipers deployed along that route,” said Heintze, founder and CEO of Hillard-Heintze, a Chicago-based security consulting firm.

“At the same time, at each building that has windows that oversee that route, there is an assessment phase that takes place. Who’s in these buildings? What’s the risk here? What other steps can we do to prevent an opportunity for somebody to take advantage of? It’s a whole process. It’s not a quick fix.”

Contributing: Associated Press