Mystery still surrounds a massive ‘sonic-like boom’ that startled residents and shook house windows in Horncastle yesterday.
Several people contacted the News to complain about the bang which happened at 5pm on Wednesday afternoon.
One suggestion is the noise - a huge explosion like sound - was generated by Typhoon jets from RAF Coningsby which were scrambled as part of a terror alert.
However, sources have indicted that the two fighters were already flying over Kent at the time of the loud noise in Horncastle.
And, it is claimed they would not have been flying at supersonic speed so close to take off.
An RAF spokesman said they could not confirm whether the Typhoons were responsible.
Reg Pope, who lives in Boston Road, said: “I used to live in Coningsby so I’m used to the sound of jets but I’ve never heard anything like it.
“The windows rattled and the dog yelped and disappeared under the table.
“I thought it was a gun going off but it was far too loud. “
Alan Marshall, said: “I was near St Mary’s when suddenly there was this loud bang.
“It sounded like a massive firework exploding.
“I don’t think it was the Typhoon because they were flying south so they wouldn’t be over Horncastle.
“It was quite frightening.”
One aviation source told the News that American F15 fighter jets could have caused the noise, but there was no confirmation from the US Air Force.
Wednesday’s alert - sparked by a Latvian cargo plane - highlighted RAF Coningsby’s importance as a frontline base.
The RAF refused to comment on allegations one of the Typhoon pilots had warned the three-man crew of the cargo plane that they risked being ‘shot down’.