Jacob England, Alvin Watts
The suspects in the Tulsa, Okla., shooting spree were arraigned on Monday, and pleas of not guilty were entered for both defendants Jake England and Alvin Watts. Reuters/Handout

Oklahoma police said two white men were arrested early Sunday as suspects in shootings that left three people dead and two others critically wounded, all black, in the Tulsa area.

One of the suspects had noted on his Facebook page that his father had been killed by a black man two years earlier.

Tulsa police spokesman Jason Willingham said police weren't prepared to label the shootings racially motivated hate crimes after the arrest of Jacob England, 19, and Alvin Watts, 32, on murder charges just before 2 a.m. Central Time Sunday.

At this point we don't have a motive, Willingham said, Reuters reported. Obviously there's still a lot of investigation to do. Hopefully in the coming days we'll be more clear on what exactly the reason was.

He said police acted on an anonymous tip and went to one location and followed the suspects after they'd traveled about a half mile on foot to another place where they were apprehended, without offering any resistance.

Willingham said England and Watts were taken early Sunday for questioning at a downtown Tulsa police station and would be booked and then jailed. It wasn't known if either had gotten an attorney yet.

We're not exactly sure what their relationship is to another, whether they are friends or extended family members, Capt. Jonathan Brooks told CNN.

About 30 agents of four law enforcement agencies -- the Tulsa police, the Tulsa County Sheriff's Office, the U.S. Marshals Service and the FBI -- had been working around the clock looking for the person that authorities say killed three people and wounded two others in shooting attacks early Friday.

It took a lot of work, a lot of collaborations between several different agencies, and a lot of help from the community, Brooks said.

At the house listed as the address for both suspects on their arrest reports, a couple who identified themselves only as England's relatives told CNN England's father had been shot to death two years ago, and he had been left to care for his 6-month-old child after his girlfriend shot and killed herself in front of him a few months ago.

His mind couldn't take it anymore, I guess, the man who called himself England's uncle told CNN, adding, I guess it just snapped his mind.

A man who is identified on England's Facebook page as his father, Carl England, was fatally shot April 5, 2010, a quarter-mile east of where shooting victim William Allen's body was found early Friday, the Tulsa World reported.

The man arrested in Carl England's killing, Pernell Demond Jefferson, was charged with pointing a firearm and is serving a prison sentence through October 2014, according to Oklahoma Department of Corrections records. Jefferson is black.

England makes several references to the two-year anniversary of his father's death on his Facebook page, including a post at 3:04 p.m. Thursday that says, Today is two years that my dad has been gone shot by a f------ n----- it's hard not to go off between that and sheran I'm gone in the head.

England's Facebook page indicates that his girlfriend, Sheran Hart Wilde, recently died. Her death notice was published Jan. 12 in the Tulsa World.

We're very pleased that this is coming to an end, at least this portion of this whole process, but we still have to remember that three of our fellow citizens were killed and their families, on Easter morning, are now having to deal with that, Tulsa Mayor Dewey Bartlett told CNN Sunday.

Willingham said the arrests followed a crime-stoppers tip Saturday, but he declined to specify what that information was. Willingham said he didn't have any immediate details when asked if the men were armed when they were arrested. But he said authorities had begun tracking the suspects Saturday evening.

We've been on them since early in the evening (of Saturday). We had been doing surveillance and using a helicopter, he told AP.

Willingham said a special operations team and other law enforcement agents were key in making the arrests. He says police used surveillance and other techniques and a helicopter in the course of apprehending the men.

Asked if the two men were armed when they were taken into custody, the police spokesman said he had no immediate information.

After the shootings, a survivor described the suspect as a white man, driving an older white pickup truck, said Tulsa Police Chief Chuck Jordan.

Brooks, the police captain, said such a truck had been spotted at at least three of the shooting sites around the time of the attacks. It has been recovered.

Police now believe both England and Watts were in the truck at the same time during the shootings, Brooks said. It appeared to have been ditched, he said.

The first shooting occurred at 1:03 a.m. Friday. That victim, 49-year-old Dannaer Fields, died at a hospital.

Three minutes later, two other people were shot, authorities said. One of them was pretty close to the (gunman's) vehicle and the other ... a little further away, said Brooks, the police captain. Those two were initially in critical condition but, by Saturday evening, were expected to survive, he said.

Then, just before 2 a.m., another person was shot and killed.

The body of a third person was found around 8 a.m. next to a funeral home in a more commercial district, though Brooks said police believe he was shot much earlier.

Police haven't begun ballistics tests to determine whether the same gun was used in all the shootings.

In addition to Fields, Jordan identified the other two victims as William Allen and Bobby Clark.

It appears all the victims were out walking or in the yard, Brooks said. This (happened in) a residential neighborhood, predominantly single-family dwellings, except for the last victim.

The Rev. Warren Blakney, a pastor at a city church and president of the NAACP's Tulsa branch, said the shootings could well prove to be hate crimes given that they happened in a predominantly black neighborhood.

For a white male to come that deep into that area and to start indiscriminately shooting, that lends itself for many to believe that it probably was a hate crime, Blakney told CNN.