BANGOR, Maine — A father and daughter smuggled cocaine and oxycodone pills to the Dexter area for 12 years by hiding it in the gas tanks, door panels, speaker boxes and taillights of cars they purchased in Rhode Island, according to testimony Monday.

Roger Belanger, 58, of Corinna and his daughter, Kelli Mujo, 30, of Wellington and Central Falls, Rhode Island, each are charged with conspiracy to distribute and to possess with the intent to distribute at least 5 kilograms, or 11 pounds, of cocaine and an unspecified amount of oxycodone and with using or maintaining a drug-involved place between Jan. 1, 2002, and Nov. 22, 2014.

Their trial before a jury of eight women and six men, including two alternates, began Monday in U.S. District Court in Bangor.

If the jury finds the father-daughter duo guilty of cocaine trafficking, it also will have to weigh in on the amount distributed. If Belanger and Mujo are found to have distributed at least 5 kilograms, they would face mandatory minimum sentences of 10 years.

Belanger and Mujo were indicted in April 2015 along with eight people who have since pleaded guilty. Seven of them are listed as potential witnesses for the prosecution.

The cocaine and oxycodone ring began operating out of Belanger’s car repair business in Garland, according to Michael Thompson, who is serving a nearly seven-year sentence for a March 10, 2012, pharmacy robbery in Guilford. Thompson, 28, of Levant testified that he started selling cocaine for Belanger as a 16-year-old.

Thompson also said that Belanger moved to California in 2004 or 2005 and that Mujo ran the drug-distribution ring until her father’s return in 2008.

Russell Beckwith, 42, of Brewer told jurors that he started selling cocaine in 2005 to support his drug habit. Beckwith, who has not been charged, testified that he made eight trips to Rhode Island with Mujo to bring drugs back to Maine.

Beckwith said that more than once he removed a package of cocaine about “the size of a Bible” from cars in which it was hidden. He also told the jury he saw Mujo break the cocaine down into smaller packets for distribution.

The U.S. Drug Enforcement Administration obtained court orders in August 2014 to wiretap the cellphones of Belanger, Mujo and other members of the conspiracy, according to court documents. Excerpts from wiretaps are expected to be played during the trial, which is expected to last 10 days.

Belanger and Mujo are free on bail with restrictive conditions that include electronic monitoring and home detention.

If convicted, Belanger and Mujo face between 10 years and life in prison on the drug conspiracy charge because of the amount of cocaine allegedly distributed and a fine of up to $10,000.

On the charge of using or maintaining a drug-involved place, they face up to 20 years in federal prison and a fine of up to $500,000.