‘‘I can't stress enough how strong that link is,'' Bejarano said.
The chief added as of Friday afternoon no motive had been determined in the case.
However, he said at that time he was unsure what if any information Westerfield had provided to police following his arrest.
Police had yet to find Danielle as of Friday and were following up on some 600 tips in the case, among them, leads that led investigators to Tijuana to search an area of that border city.
Bejarano told reporters he remains optimistic that Danielle will be found.
Westerfield was a suspect in the case from the start with police questioning him, seizing his motor home and a sport-utility vehicle.
They also had Westerfield lead investigators into the Imperial Valley where he reportedly spent time in the Glamis area on Feb. 3, a day after Danielle's disappearance.
Police have searched the northeastern and western deserts of Imperial County.
A San Diego police spokesman said late Friday he is unaware of any plans to return to the Imperial Valley to continue to investigate the desert.
Volunteer searchers from the American Sand Association conducted another search of the Glamis area one week ago.
Jernigan said Friday of the Imperial County Sheriff's Office, "We are continuing to investigate all leads at the request of San Diego authorities."
He did not speak specifically as to how the department is continuing to assist in the investigation.
He said only that "we are doing everything humanly possible to help them."
Jernigan did say he wanted to give credit to Susie Cramer Green, general manager of the Carl's Jr. restaurant on 32nd Street in Yuma, stating she has been providing food to searchers from the Sheriff's Office.
In San Diego, Danielle's parents said while police may have made an arrest, they still do not have any word on their daughter.
‘‘We are very happy that police have made an arrest … But the fact still remains that we don't have our daughter. We still need to find Danielle,'' the girl's mother, Brenda van Dam, said outside the family home.
Westerfield, a self-employed engineer and divorced father who lives two doors from the van Dams, appeared calm as he was led into an unmarked police car.
Damon van Dam, Danielle's father, has said the family did not know Westerfield well.
‘‘He's an acquaintance. He's not a friend,'' Damon van Dam said. ‘‘We've seen him since we moved in. We wave to him. We say hello to him when we drive by.''
Calls to Westerfield's attorney were not immediately returned.
Westerfield has told reporters that he saw Brenda van Dam at a bar near their home the night before Danielle was reported missing. Westerfield also said he went away that weekend to the Imperial County desert.
Danielle was last seen when Damon van Dam put her to bed about 10 p.m. Feb. 1. He stayed home with Danielle and her two brothers while Brenda was at the bar.
Brenda van Dam came home around 2:30 a.m., then stayed up for an hour with her husband and friends. She said she made sure the children's bedroom doors were closed to keep from disturbing them, but didn't check on the children.
Danielle's disappearance was featured on the crime-fighting show ‘‘America's Most Wanted.''
On the Net: www.daniellemissing.com
>> Staff Writer Darren Simon can be reached at 337-4082.