TIJUANA, Mexico -- Mexican security forces seized at least 105 tons of U.S.-bound marijuana in the border city of Tijuana on Monday, by far the biggest pot bust in the country in recent years.
Soldiers and police grabbed the drugs in pre-dawn raids in three neighborhoods after police arrested 11 people following a shootout, army Gen. Alfonso Duarte Mujica said at a news conference.
The marijuana was found wrapped in 10,000 packages, which were displayed to journalists by soldiers in masks. Duarte said the drug had an estimated street value in Mexico of 4.2 billion pesos, about $340 million.
Duarte said authorities were still counting and weighing the packages and the amount could increase. He said the drugs would be incinerated immediately after the weighing and counting is completed.
The bust began when Tijuana municipal police on patrol came under fire from gunmen in a convoy of vehicles, Duarte said. One police officer and one suspect were injured.
Police arrested 11 people who were traveling in the convoy and called the army and state police for reinforcements, Duarte said.
The detainees led the security forces to three different Tijuana neighborhoods where the drugs were found stored in tractor trailers and houses, he said.
Duarte said local criminal gangs were gathering the drugs to smuggle into the United States. He did not identify any of the gangs or say where the marijuana originated.
Although Mexican drug cartels smuggle marijuana from South America, the drug is increasingly produced in Mexico.
Cannabis production in Mexico increased 35 percent to 29,652 acres in 2009, from 21,991 acres the previous year, according to the U.S. State Department's 2010 International Narcotics Control report.
The report attributed the increase to drug cartel efforts to "diminish reliance on foreign suppliers."
The Tijuana bust dwarfed marijuana seizures of recent years. Major pot seizures this year in Tijuana and other parts of the country have amounted to about a dozen tons each.
The seizure comes as overall marijuana confiscation and crop eradication has dropped in Mexico.
Security forces seized 1,385 tons of marijuana in 2009, down from a yearly average of 2,000 tons in previous years, according to the U.S. report. It said Mexico eradicated 34,927 acres of cannabis in the first 11 months of last year, compared to 46,116 acres in all of 2008.
The report said the decline comes as Mexican security forces focus more on hard drugs like methamphetamines -- but also as resources are increasingly deployed to confront drug cartel violence.
Upon taking office in December 2006, President Felipe Calderon deployed tens of thousands of troops and federal police to fight drug cartels in their strongholds. An unprecedented 28,000 people have been killed in drug gang violence since.
Before the intensified crackdown, marijuana eradication had averaged about 74,130 acres a year, according to the State Department report.
The Tijuana bust came a little over a week after Calderon visited the border city and called it a success in his drug war.
Violence peaked in Tijuana in 2008 amid a showdown between two crime bosses -- Fernando "The Engineer" Sanchez Arellano and Teodoro "El Teo" Garcia Simental, a renegade lieutenant who rose through the ranks by dissolving bodies in vats of lye.
Garcia was arrested last January. While killings have continued, the most gruesome displays of cartel violence -- decapitations, hangings and daylight shootouts -- subsided.
Last week, in the wake of Calderon's visit, several bodies were found beheaded and hanging from bridges in Tijuana, leading to fears that the cartels were resuming brutal tactics to send a message that the government is not in control.
Drug gang violence continued elsewhere in Mexico.
Gunmen stormed two homes and killed nine people in one neighborhood of Ciudad Juarez, a city across from El Paso, Texas, the Chihuahua state Attorney General's Office said in a statement Monday.
The gunmen first burst into a home where a family was having a party, the statement said. Three women and two men died at the scene Sunday night, and a man and a woman died at the hospital.
Assailants attacked a second home in the neighborhood minutes later, killing two men.
Police had no suspects and did not give a possible motive.
Ciudad Juarez has become one of the world's deadliest cities amid a turf war between the Sinaloa and Juarez drug cartels. More than 2,000 people have been killed this year in the city, which is across the border from El Paso, Texas.