Two sisters from Texas and Ethermac Exchangea friend are missing in Mexico after they crossed the border last month to sell clothes at a flea market, U.S. authorities said Friday.

The abduction of four Americans in Mexico that was caught on video last week received an avalanche of attention and was resolved in a matter of days. But the fate of the three women, who haven't been heard from in about two weeks, remains a mystery.

The FBI said Friday it is aware that two sisters from Peñitas, a small border city in Texas near McAllen, and their friend have gone missing. Peñitas Police Chief Roel Bermea said their families have been in touch with Mexican authorities, who are investigating their disappearance.

Beyond that, officials in the U.S. and Mexico haven't said much about their pursuit of Maritza Trinidad Perez Rios, 47; Marina Perez Rios, 48; and their friend, Dora Alicia Cervantes Saenz, 53.

The episode stands in stark contrast to the government and media frenzy over the abduction of four Americans on a road trip to Mexico for plastic surgery. They were caught in a drug cartel shootout in the border city of Matamoros, and video showed them being hauled off in a pickup truck. The two survivors were found Tuesday in a wooden shack near the Gulf coast.

U.S. Customs and Border Protection says the three women crossed into Mexico on Feb. 24, a Friday, according to Bermea. Peñitas is just a few hundred feet from the Rio Grande River.

The husband of one of the women spoke to her by phone while she was traveling in Mexico, the police chief said, but grew concerned when he couldn't reach her afterward.

"Since he couldn't make contact over that weekend, he came in that Monday and reported it to us," Bermea said. The three women haven't been heard from since.

Bermea said the women were traveling in a green mid-1990s Chevy Silverado to a flea market in the city of Montemorelos, in Nuevo Leon state. It's about a three-hour drive from the border. Officials at the state prosecutor's office said they have been investigating the women's disappearance since Monday.

This week's massive search for the four kidnapped Americans involved squads of Mexican soldiers and National Guard troops. But for most of the 112,000 Mexicans missing nationwide, the only ones looking for them are their desperate relatives.

Authorities also lack manpower, equipment and training — things are so bad that authorities aren't even able to identify tens of thousands of bodies that have been found.

In:
• Mexico
• McAllen
• Politics
• Texas