The loud boom heard throughout Howard and Tipton counties late Wednesday was caused by F-16 fighter jets conducting training in the area, the Indiana National Guard reported Thursday.

Howard and Tipton county police and fire units scrambled to the area of U.S. 31 and 300 North in Tipton County about 10:30 p.m. Wednesday, upon hearing numerous reports of a loud boom and strange lights in the sky.

In Howard County, 911 dispatchers took 146 phone calls within a 15-minute timeframe between 10:25 and 10:40 p.m. Normally the 911 center averages 15-20 calls per night.

Initially, police thought it was an aircraft crash. But without any evidence of a crash or any debris, police were left puzzled.

Speculations ran rampant that the boom and bright lights were either a plane crash, a meteor shower and even UFOs were mentioned as the culprits.

A representative of the Indiana National Guard in Indianapolis said Thursday that the guard takes responsibility for the recent nighttime disturbance in Kokomo and Logansport the past two days.

“Loud noises reported by citizens in northern Indiana accompanied by flashes of light and what appeared to be falling debris early this week were a result of training conducted by Indiana National Guard F-16 Aircraft, headquartered at Fort Wayne’s 122nd Fighter Wing,” a press release from Col. Jeffery Soldner, commander of the 122nd Fighter Wing, stated.

The Indiana Air National Guard conducts training missions on a daily basis.

“All of our military members, including our pilots and crewmembers, require the most realistic training possible for their own safety and those they work to protect,” Soldner said.

The release explained that F-16 aircraft routinely train with the countermeasure Chaffe-flare system which draws heat-seeking missiles away from the aircraft exhaust.

It was the nighttime engagement of this system that resulted in the “strings of lights” reported by citizens, according to the release.

The flares were released above 10,000 feet in accordance with the long-standing guidance for the Hilltop Military Operations Area that extends from Grissom Air Reserve Base to West Lafayette and includes Logansport, 30 miles north of Indianapolis bordering Kokomo.

Soldner also said the area is not designated for “super-sonic” flight and an investigation will be conducted to determine if any aircraft exceeded that speed.

“I have ordered a thorough investigation to be conducted into why the incident took place,” he said in the release. “I have also ordered that our Flying Squadron conduct a complete review of the tactics that were in practice at the time. We will ensure that our pilots review airspeed restrictions in all of our practice flight training areas, and that these restrictions are briefed prior to each flight.”

Larry Smith, director of the Howard County Emergency Management Agency, said his officers were ready in case any wreckage was found.

“We started activating our guys when the sheriff department called,” Smith said of the incident. “We set up at U.S. 31 and Ind. 26 since we heard it may have come from 300 North area in Tipton County. Then we heard it may be in the area of Clinton and Howard county line so we set up a grid search of the area and found nothing.”

Smith’s secretary, Janice Hart, said she was lying on her bed talking to her niece when a loud explosion rocked her home.

“It just shook my house to its depths. As soon as it happened, my niece said, ‘Oh my God, Aunt Janice, what was that?’ I looked out my bedroom window and my husband went to the front of the house to see what it was,” she said.

Hart, who initially thought an explosion had rocked a nearby factory, was busy Thursday morning handling calls about the noise and lights.

“That’s all they’re talking about. I had numerous calls asking if it was a sonic boom, a meteor, even some people joking that it was a UFO,” she said.

Logansport Police Chief A.J. Rozzi said he heard a loud sonic boom Tuesday night and then heard the sound of a jet high overheard. He said residents also reported seeing fire streaks in the sky.

He said it is common for the 122nd to conduct missions in the area and believes F-16 training almost certainly explains the sights and sounds.

“They’ve been doing that training for quite a while. I don’t know what maneuvers they’re actually doing, but they do shoot out streaks of light,” he said.

The Associated Press contributed to this report.