Story highlights A tractor and fire engine in a fatal Maine parade crash had been rerouted

The tractor driver died after being hit by a fire truck during the Bangor, Maine, event

A boy either fell or jumped off a float in Edmond, Oklahoma, police say

The boy was run over by a trailer being towed by his father, according to police

An 8-year-old boy died when a trailer being pulled by his father ran over him during an Oklahoma Fourth of July parade, while a man driving a tractor died in a collision with a vintage fire truck in another parade nearly 2,000 miles northeast.

The young boy either fell or jumped off the float late Thursday morning and was run over by the trailer carrying it, according to police in Edmond, which is about 15 miles north of Oklahoma City.

The boy's father was in the truck that was towing the trailer, which was filled with hay and decorated by small patriotic garland along its edges. The float had a martial-arts theme, according to police spokeswoman Jennifer Monroe.

The father rushed out of the vehicle, and he and a nurse who had been riding in a car behind the float performed CPR on the child, police said.

Video from CNN affiliate KFOR later showed first responders along the road, which appeared to be bordered by trees, and moving a stretcher with the child into an awaiting ambulance.

The boy was later pronounced dead at a hospital, Monroe said.

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"Our thoughts today for the family of a 7 yr old boy killed in a float accident at the end of the LibertyFest parade," Edmond police said Thursday in a tweet . "Heartbreaking."

Money magazine a few years ago listed Edmond, a city of about 81,000 people, as 35th on its list of America's best small cities. The annual LibertyFest festivities around Independence Day -- highlighted by the parade -- was singled out as a "must-go event" in the city, according to the publication, which like CNN is a division of Time Warner.

The Edmond incident wasn't the only parade fatality this Independence Day.

A man driving a green tractor in Bangor, Maine, died instantly Thursday afternoon after a vintage fire truck hit him from behind, police said in a statement. Both vehicles were part of the Bangor-Brewer July Fourth parade, which is the state's largest such parade with more than 1,000 participants and 30,000 spectators, according to Gov. Paul LePage

Police officers in the city's accident reconstruction team, evidence response team and criminal investigations division -- as well as the medical examiner's office and a Maine State Police member -- are assisting in the investigation, according to Bangor police.

Police Sgt. Paul Edwards explained that the parade was rerouted because of a four-hour standoff in Bangor with a man who'd shot a gun, prompting a woman and her baby to run for help.

"They would not have been on that street normally," Edwards said of the people driving the tractor and fire truck.

The suspect fired several rounds at police from a second-floor apartment window, with authorities responding with several rounds of their own and tear gas.

The man -- identified by police as 43-year-old Perrin Oliver -- was taken into custody around 12:20 p.m. and charged with criminal threatening and aggravated reckless conduct with a firearm, both felonies. Edwards, the Bangor police spokesman, said he doubts Oliver will face additional charges tied to the tractor driver's death.