Police in Tennessee arrested the mother and ex-wife of Adam Mayes, the man suspected of kidnapping a mother and her three children, state authorities said. The Tennessee Bureau of Investigation said Mayes\' mother, 65-year-old Mary Frances Mayes, and his ex-wife, Teresa Ann Mayes, were in jail after being arrested Monday, CNN reported Tuesday. Teresa Mayes was charged with four counts of especially aggravated kidnapping and Mary Frances Mayes was charged with four counts of conspiracy to commit especially aggravated kidnapping. The bodies of Jo Ann Bain and her oldest daughter, 14-year-old Adrienne, were found last week at a home in Guntown, Miss., that has been tied to Adam Mayes, TBI officials said. Investigators still are searching for Mayes and Bain\'s two younger daughters, Alexandria, 12, and Kyliyah, 8. An arrest warrant indicated Teresa Mayes admitted driving a vehicle in which the mother and her three daughters were riding from Hardeman County, Tenn., to Union County, Miss. At least 17 law enforcement agencies are involved and hundreds of people are working on the investigation, FBI Special Agent Joel Siskovic said. Siskovic declined to speculate on a possible motive, saying the focus for now was on finding the missing girls. \"We are absolutely hopeful [about the girls\' being alive]. Currently that\'s what we believe, and we do believe that they are still with Mayes,\" Siskovic said. Bobbi Booth, Teresa Mayes\' sister, told CNN that she\'s known Adam Mayes for 25 years and \"he\'s always been weird and unusual ... but I never dreamed he would do something like this.\" She described him as an aggressive and untrustworthy man who had beat and threatened to kill her sister. Booth also pleaded on-air for Mayes to \"do the right thing.\" \"Just let the children go. This has gone on way too far. And we need to figure out what\'s going on, and it\'s not fair to the children,\" she said. Adam Mayes, 35 and white, is considered armed and dangerous. Authorities have asked for the public\'s help in locating him and the two girls. Authorities had contacted and tried to interview Mayes soon after the mother and daughters were reported missing April 27 by Jo Ann Bain\'s husband in Whiteville, Tenn. After determining that some information he had given was misleading, police tried to re-interview Mayes, but he had fled. Mayes was last seen May 1 in Guntown, where the bodies were found. Authorities in Mississippi maintained checkpoints to stop and search cars, state Highway Patrol Master Sgt. Johnny Poulos said. While the focus is on Union County, where Guntown is located, authorities said Mayes has ties to Texas, North Carolina, South Carolina and Florida, and could be traveling to Arizona.