The official said the motive behind the killing remains unclear.

Officials with the US Embassy P90X in Mexico City declined to comment. At the US Justice Department in Washington, spokeswoman Tracy Schmaler law enforcement "continues to work closely with our Mexican counterparts to bring to justice individuals involved in these murders." US Embassy officials previously said that Enriquez was never in a position to provide visas and worked in a section that provides basic services to US citizens in Mexico. Mexican police provided no further details from Chavez's confession on how Enriquez might have helped provide visas to a drug gang. Enriquez was four months pregnant when she and her husband, Arthur H. Redelfs, were killed by gunmen who opened fire on their vehicle after the couple left a children's birthday party. Their 7-month-old daughter was found wailing in the back seat. Jorge Alberto Salcido, the husband of a Mexican employee of the consulate, also was killed by gunmen after leaving the same event in a separate vehicle.

Chavez told police that gunmen ray ban opened fire on Salcido because the two cars were the same color and the hit men did not know which one Enriquez was in, Pequeno said. Investigators also have looked at whether Redelfs may have been targeted because of his work at an El Paso County jail that holds several members of the Barrio Azteca, the gang believed to be responsible for the attacks. Pequeno said Chavez belongs to Barrio Azteca, which works for the Juarez cartel on both sides of the border. In March, US federal, state and local law enforcement officers swept through El Paso, picking up suspected members of the gang in an effort to find new leads in the killings. A suspect detained in Mexico shortly after the shooting confessed to acting as a lookout as the Azteca gang supposedly hunted down Redelfs, but he was never charged and was released without explanation. Officials also have speculated that both attacks could have been a case of mistaken identity.

More than 23,000 people have been blower killed in Mexico's drug-related violence since President Felipe Calderon launched an all-out offensive against drug gangs in 2006. Much of the violence stems from rival drug- and migrant-smuggling gangs vying for power, including a firefight Thursday that left 21 people dead and at least six others wounded about 12 miles (20 kilometers) from the Arizona border.

An explosion caused by a torpedo likely tore apart and sank a South Korean warship near the Democratic People's Republic of Korea (DPRK) border, Seoul's defense minister said Sunday, while declining to assign blame for the blast on Pyongyang.

Defense MinisterGHDS Kim Tae-young said an underwater explosion appeared to have ripped apart the vessel, and a torpedo blast seemed the most likely cause. Investigators who examined salvaged wreckage separately announced Sunday that a close-range, external explosion likely sank it. "Basically, I think the bubble jet effect caused by a heavy torpedo is the most likely" cause, Kim told reporters. The bubble jet effect refers to the rapidly expanding bubble an underwater blast creates and the subsequent destructive column of water unleashed. Kim, however, did not speculate on who may have fired the weapon and said an investigation was ongoing and it's still too early to determine the cause. Soon after the disaster, Kim told lawmakers that a DPRK torpedo was one of the likely scenarios, but the government has been careful not to blame the North outright, and Pyongyang has denied its involvement. The Cheonan was on a routine patrol on March 26 when the unexplained explosion split it in two in one of South Korea's worst naval disasters. Forty bodies have been recovered so far, but six crew members are still unaccounted for and are presumed dead.

The site of thesunglasses sinking is near where the rival Koreas fought three times since 1999, most recently a November clash that left one DPRK soldier dead and three others wounded. The two Koreas are still technically at war because their 1950-53 Korean War ended in a truce, not a peace treaty. Also Sunday, investigators said a preliminary investigation of the front part of the 1,200-ton ship _ retrieved the day before _ pointed to an external explosion. Chief investigator Yoon Duk-yong told reporters that an inspection of the hull pointed to an underwater explosion. He appeared to support the bubble jet effect theory, saying, "It is highly likely that a non-contact explosion was the case rather than a contact explosion." But he, too, said it was too early to determine what caused the explosion. Earlier Sunday, Prime Minister Chung Un-chan said South Korea will take "stern" action against whoever was behind the explosion as the country started a five-day funeral for the 46 dead and missing sailors. Makeshift alters were set up in Seoul and other major cities to allow citizens to pay their respect.

"We will remember Ray Ban sunglassesall of you in the name of the Republic of Korea to let you keep alive in our hearts," said Chung, clad in a black suit and tie. The 46 sailors will be promoted by one rank and awarded posthumous medals, he said.