(CNN) -- A Washington woman who hid a sedated monkey under her blouse on a flight from Thailand was convicted of violating wildlife laws for smuggling the monkey into the United States, prosecutors said Tuesday.

Authorities rescued the monkey from Gypsy Lawson's fake womb.

Gypsy Lawson, 28, and her mother, Fran Ogren, 56, were convicted of smuggling and conspiracy to smuggle the monkey in violation of the Endangered Species Act and other federal laws.

Lawson hid the young rhesus macaque monkey under a loose-fitting blouse on a flight from Bangkok, Thailand, to Los Angeles, California, International Airport, pretending she was pregnant, the U.S. Attorneys Office for the Eastern District of Washington said.

Permits are required to possess rhesus monkeys and many other species of animals. Such permits are granted for research, enhancement and conservation purposes. Additionally, transporting such species into the United States requires a customs declaration. Lawson and Ogren had neither.

"These defendants purposely undertook a course of action which could well have endangered many citizens, as well as the life of the animal in question," said U.S. Attorney James McDevitt.

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Rhesus monkeys are known to carry viruses and parasites that can be transmitted to humans, said Paul Chang, a U.S. Fish and Wildlife Service agent.

"This particular animal tested negative," he said.

Chang said the monkey has been placed with a rescue center for abandoned primates, "but it could have been living out its life with its family in its native habitat."

Authorities found journals and handwritten notes describing the mother and daughter's attempts to find a monkey small enough to smuggle back to the United States. The journal also described the pair's "acquisition of a small monkey and their experimenting with different medicines to sedate the monkey for their journey home," McDevitt's office said.

Authorities also found photographs of Lawson at two airports and on an airplane in which she is wearing loose-fitting clothing and appears to be pregnant.

"The journal confirms that she and her mother smuggled the monkey into the United States by hiding it under her shirt, pretending she was pregnant in order to get past authorities," the statement from McDevitt's office said.

Co-defendant James Edward Pratt, 34, already has pleaded guilty to misdemeanor charges of possession and transportation of prohibited wildlife. He will be sentenced in January.

Sentencing for Lawson and Ogren is scheduled for March 3, 2009. The smuggling conviction carries a maximum sentence of 20 years in prison, a $250,000 fine and up to three years of court supervision after release. The conspiracy charge carries a maximum of five years in prison, a $250,000 fine and up to three years of court supervision after release.

Flight itineraries show the pair flew from Spokane, Washington, to Bangkok on November 4-5, 2007, with stops in Seattle, Washington, and Inchon, South Korea. They returned on a direct flight from Bangkok to Los Angeles, California, on November 28, 2007.

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