DENVER -- A Jefferson County school tutor was seriously injured when her car was hit by an unmarked pickup truck driven by a Denver police detective during a chase near an elementary school Wednesday afternoon.

Edith Mack's car flipped onto its top after it was hit in the intersection of Ninth Avenue and Gray Street, two blocks from Molholm Elementary School, where she works.

The undercover detective who was driving the truck was not injured.

Witnesses said they did not hear sirens as the chase roared through the quiet neighborhood.

Police said the incident began at 3:40 p.m. when members of the Safe Streets Task Force were staking out a southwest Denver home, in the 200 block of South Zenobia Street, to look for a suspect in a string of armed robberies in the Denver area.

The suspect, identified by police as Manuel Santistevan, 26, was observed by officers fleeing the house with an unidentified woman in a white sport utility vehicle.

That's when undercover officers began pursuing the SUV, chasing it into nearby Lakewood. Click here for a link to radio transmissions of the chase.

The chase went through a four-way stop two blocks from Molholm Elementary. Mack was headed home from school when her car was hit by the undercover officer's pickup truck.

The impact flipped it, pinning her upside down.

Mack was trapped in the wreckage for a half-hour before she could be removed and transported to St. Anthony Central Hospital where she was treated for pelvic injuries. She was listed in fair condition Thursday.

Santistevan escaped and was still at large Thursday. Police said he and the passenger abandoned the SUV at West 14th Avenue and Lamar Street and fled on foot. Police said he is a suspected member of a robbery ring named the Hooded Safe Bandits, who are responsible for as many as 20 holdups in the Denver metro area.

Witnesses blame Santistevan for the crash.

"He had no regard for anyone else. This is probably not the first time that he's been involved in a chase," said Ken Robertson.

The Denver office of the FBI announced Thursday that it was offering a "significant" reward for information leading to Santistevan's arrest.

Anyone with information was asked to call Crime Stoppers at 720-913-7867 or the FBI at 303-629-7171.

Did Chase Violate Department Policy?

Detective John White said Denver police will conduct an internal investigation to determine whether the officers violated the department's chase policy.

7NEWS obtained a copy of the department's policy.

The policy said that officers can chase suspects if the suspect poses an immediate threat to the public. According to the policy, the officer is justified because the suspect "was involved in a felony with a deadly weapon."

However, the policy prohibits a vehicle without lights and a siren from pursuing a suspect. Denver police said the undercover detective's truck was not equipped with emergency signals or sirens.

The policy also said the pursuing officer needs to consider factors such as if the area they are racing through is in a school zone, in a densely populated area with pedestrians, or in a residential neighborhood.

The policy also states that a pursuing officer needs to consider whether the suspect is known, because if he is, then he could be arrested later.

"The Denver pursuit policy is very detailed and quite restrictive and it is considered to be a best practice nationwide," said Denver police monitor Richard Rosenthal.

Because the crash occurred in Lakewood, Lakewood police will be in charge of the investigation.

The undercover detective is a member of the DPD's fugitive unit and has been with the police department since 1997. His work status has not changed and he has not been placed on leave.

This is the second Denver police chase in less than a week that has resulted in a crash.

Victim Hit On First Day Of School

Mack was returning from a meeting at Molholm Elementary, where it was the first day of school, when she was sideswiped.

"Considering what the crash site looked like, she's doing remarkable. She does have a fracture to her pelvis but they were going to stand her up and assess the therapy," said Molholm Elementary principal Joan Chavez.

Mack has worked at Molholm for 10 years and is so dedicated that she called the school on Thursday to apologize for not being at work.

"She is originally from Mexico and so she has a really good link with our kids who are learning English, and also our families. She's really dedicated," Chavez said.