FORT WORTH, Texas » Investigators have run down “hundreds and hundreds” of leads in the search for “affluenza” teen Ethan Couch, Tarrant County Sheriff Dee Anderson said today, but still have no solid information on his whereabouts.

“Some of the leads we get are not really useful at all,” Anderson said at a joint news conference with Tarrant County District Attorney Sharen Wilson. “But we don’t want that to discourage people from sending in tips. We want any information anyone thinks is good for us.”

Anderson and Wilson displayed photos released by the U.S. Marshals Service of a black Ford F-150 pickup similar to one belonging to Ethan Couch’s mother, Tonya Couch.

Anderson said authorities suspect the mother and son are together, but they haven’t been able to prove it.

“There’s a possibility they may be in that truck,” Anderson said. “If we know it’s not in that truck, we can cross that off our list.”

Tonya Couch was added to a missing persons list Sunday. Anderson said the missing persons report filed by Tonya Couch’s mother gave authorities “a leg up on getting her into the national computer system.”

Anderson said he and the district attorney’s office have discussed naming Tonya Couch as a suspect in aiding her son’s escape, but “we’re not to the point where we can say that.”

Ethan Couch, 18, has been on the run since reportedly missing an appointment with a probation officer. He’s serving 10 years of probation for drunkenly killing four people in a 2013 wreck.

Couch, who turns 19 in April, was 16 when he lost control of his Ford F-350 pickup on June 15, 2013, and plowed into a group of people helping a woman whose car had stalled on Burleson-Retta Road in southern Tarrant County.

Since Couch was prosecuted as a juvenile, the specific terms of his probation can’t be revealed. But Wilson said staying within the county is a requirement of probation applied to all juveniles.

“As a juvenile being on probation, the problem is that he’s not here,” Wilson said. “They have to ask permission to leave the county. … Yes, it’s a violation of his probation.”

Couch’s disappearance came while Wilson’s office was investigating a video of him allegedly partying around a beer pong table. A six-second clip posted to Twitter on Dec. 2 showed a person resembling Couch standing next to the table, clapping as someone dove onto the table.

When asked today whether it was Couch in the video, Wilson said, “Well, it certainly looked like him.”

Tarrant County Juvenile Services issued a directive to apprehend — essentially a juvenile arrest warrant — for Couch on Dec. 14.

The sheriff department’s fugitive unit began searching for him Dec. 15 after receiving the warrant.

The U.S. Marshals Service, which joined the search for Couch last week, issued a wanted flier Friday. It says a reward of up to $5,000 “is offered for information that leads to the whereabouts and arrest of Couch.”

Authorities have reviewed bank, phone and airplane records. Anderson said they also followed up on a lead about Couch’s mother having an address in Georgia.

Anderson has said he “wouldn’t be shocked” if Couch fled the country.

Couch’s father, Fred Couch, met with investigators and was “polite and cooperative, but not particularly forthcoming with information,” Anderson said. Fred Couch told authorities he had not heard from his son or ex-wife in weeks.

Ethan Couch’s case gained national attention when a psychologist said he was a victim of “affluenza,” a state of reckless or irresponsible behavior brought on by wealth. State District Judge Jean Boyd, now retired, sentenced Couch to probation and therapy, including a stint at a state hospital.

Wilson said today the sentence was not a “sufficient punishment for a teenager killing four people as a drunk driver.” Anderson called it a “miscarriage of justice.”

In November, the district attorney’s office filed a motion to transfer Couch to the supervision of an adult court. Without the transfer, his probation will expire on his 19th birthday in April, under the Texas Family Code.

Couch must be present before a judge for his case to be transferred to an adult court. But if he’s caught by authorities after his 19th birthday, the district attorney’s office will still have an opportunity to transfer the case.

As an adult, Couch would be “looking at state penitentiary time” for a parole violation, Wilson said.