LIMESTONE — A Florida man who set the world record for fastest speed on a conventional motorcycle died Sunday from injuries suffered when he lost control of his motorcycle and reportedly slid 1,000 feet during a speed trial at the former Loring Air Force Base.

William “Bill” Warner, 44, a speed racer and tropical fish grower from Wimauma, Fla., was attempting to hit 300 mph within 1 mile just before 10 a.m. Sunday during The Maine Event, an annual speed trial race sanctioned by the Loring Timing Association.

The motorcyclist made it about 4,000 feet before suddenly losing control of his modified turbocharged Suzuki Hayabusa. Limestone Police Chief Stacey Mahan said Warner went off the track and into the grass, where he and his bike went into a long slide.

He was taken immediately to Cary Medical Center in Caribou, according to race officials. After the crash, the remainder of Sunday’s races were canceled.

Bill Flagg, a spokesman for the hospital, confirmed Sunday afternoon that Warner had died from his injuries at 11:15 a.m. The announcement was delayed until Warner’s family could be notified, Flagg said.

Limestone Volunteer Fire Department and Crown Ambulance were on scene in case of accidents during the time trials.

Mahan said his department, with help from race officials and Warner’s pit team, will continue to investigate the accident. He was able to provide few details on Sunday.

“There are a lot of factors we still need to look into,” he said.

Race officials interviewed immediately after the accident said Warner was “awake and talking” when he was brought to the Caribou hospital. Those officials — event director Mark Sotomayor and race director Tim Kelly — were unreachable for additional comment later in the day.

One person who watched the race from the starting line said he could tell that things had gone wrong when he saw that Warner had veered off the track to the right.

The Loring Timing Association instructs racers to veer off the track to the left if there is a vehicle problem and to veer to the right if they are injured or if their vehicle is on fire.

“He got maybe 4,000 feet or so, and where I was standing at the starting line, you could see a big dust cloud and then it got silent,” said Cole Theriault, a spectator from Connor Township. “The bike, from what I heard, was demolished, just in pieces. After a minute, all you could hear was the sirens.”

Mahan confirmed that the bike was “significantly damaged.”

Warner set a world record at the time trial in 2011, when he became the first conventional motorcyclist in history to top 300 mph, according to the Loring Timing Association. On a 1½-mile course, he maxed out at 311.945 mph. On Saturday, he broke the 1-mile record at Loring when he hit 296 mph.

In 2011, Warner spoke about the his record-breaking run.

“The big part of it, after the speed happens, is trying to stop the bike,” he said. “Here at Loring Air Force Base, there is a mile shutdown to slow the vehicles down and I used every bit of it. The bike was bouncing, hopping, skipping and sliding. Needless to say, I got it stopped safely. It was a little scary.”

According to the Loring Timing Association’s website, the track at Loring is the longest land speed record track in the world, with a total length of 2? miles, including a long stretch for cooldown.