American Lori Berenson, imprisoned in Peru for collaborating with violent leftist guerrillas, has returned to the Andean nation after being allowed her first US visit since being jailed 16 years ago. Berenson arrived at Lima\'s international airport overnight accompanied by her three-year-old son who was born in a Peru prison, and appeared startled by a swarm of media cameras awaiting her arrival from a three-week trip to the New York area, according to images on local television. The 42-year-old American was paroled in late 2010 after serving 15 years of a 20-year sentence for helping the Tupac Amaru Revolutionary Movement (MRTA) in a plot to seize congress and take lawmakers hostage. Peruvian law requires her to live in Lima for the remainder of her original sentence. Last month she was authorized by the court to travel to the United States in a window from December 16 to January 11, an authorization that triggered a controversy in Peru among the military and victims of the internal conflict of 1980-2000 that left some 70,000 people dead. President Ollanta Humala, a former officer, had expressed his \"disappointment\" after an appeals court overruled a lower court and allowed Berenson to travel, saying there was no guarantee in place that she would return to Peru as required. Berenson\'s 2010 release sparked a public outcry in Peru, where she is remembered as a defiant foreigner raising her fist and chanting leftist slogans during her trial in 1995. The MRTA has since disintegrated, with most of its members either dead or in prison following a fierce government crackdown on leftist guerrilla groups in the 1990s under then-president Alberto Fujimori.