An Arlington police officer is in critical condition 
Tuesday after being shot by a teen suspected of killing a 6-year-old 
Texas girl whose body was found wrapped in a tarp in a nearby 
residential street. The teenage suspect was shot in the head by another 
officer.
Alanna Gallagher's body was found on a
  residential  street about a mile  from her family's home in the North 
Texas  community of Saginaw on   July 1.
A law enforcement source told NBC DFW
 that police went to the home of Tyler Holder, 17-year-old neighbor, 
because DNA evidence linked him to Gallagher's slaying.
The home is in the 600 block of Babbling Brook Drive in Saginaw, a couple of houses away from Gallagher's home.
Holder came to the front door with a 
gun in his waistband, pulled it out and opened fire at the officers, a 
law enforcement source said.
Arlington police Detective Charles Lodatto, who was 
assignment with the FBI task force investigating Gallagher's slaying, 
was shot in the groin. The bullet divided his femoral artery, doctors said later Tuesday.
Holder was shot in the head and his 
condition is life-threatening, MedStar EMS confirmed. He was taken to 
John Peter Smith Hospital in Fort Worth.
Saginaw police spokesman Officer 
Damon Ing said officers were serving arrest and search warrants on the 
man they considered the main suspect in Gallagher's slaying.
Holder Arrest Warrant
The arrest warrant issued for Holder
 outlines the events that lead up to the killing of the 6-year-old and 
includes graphic details of her death.
Gallagher was found wrapped in a 
tarp with plastic grocery sacks taped over her head with duct tape. The 
warrant also states the 6-year-old was sexually assaulted.
NBC DFW has chosen not to reveal further details about the assault because of its graphic nature.
According to the warrant, Holder was seen pacing "up and down the sidewalk" when Gallagher's body was found.
Neighbors in the area told officers 
that Holder told them the body recovered was Alanna Gallagher before the
 victim had been identified.
Another neighbor also told officers 
she had seen a gray tarp in the back yard of Holder's home two to three 
months ago. At that time, officers didn't see the tarp in the back yard.
 Officers later determined that the tarp the neighbor spotted in the 
back yard was similar to the tarp in which Gallagher was wrapped.
Investigators first interviewed 
Holder on July 1, the day Gallagher was killed. The FBI then interviewed
 him on July 5 and agreed to provide a DNA sample. On Saturday, Holder's
 DNA sample matched DNA found on the victim.
The arrest warrant was issued Tuesday.
Neighbors Feel Some Relief
One of Holder's neighbors said authorities warned her hours earlier to expect some type of police activity in the area.
"I asked the detectives if I needed 
to come get my girls and take them  to my grandma's house in Grapevine,"
 said Megan Perez, a next-door neighbor. "They said they  couldn't 
really tell me anything right then but it may be a good idea, so  that's
 when I knew something was going to happen."
Perez's twin daughters regularly played with Gallagher.
Perez said she didn't expect something would happen so soon or that it would end so violently.
"It's scary to think he was so close and it could have been one of my kids," she said.
Danielle Simmons, who lives close to
 where Gallagher's body was found said she recalls seeing Holder at a 
candlelight vigil for the slain girl.
"He showed up at her memorial with a
 'wanted' shirt on, at the candlelight vigil with a 'wanted' shirt," she
 said. "How disrespectful is that?"
But residents of Saginaw, which is 
wrapped in purple ribbons in memory of Gallagher, say they feel some 
relief that a suspect has been identified.
"Our community can go back to being the way we were," Simmons said. "This is a very family-oriented community." VIDEO