CIUDAD JUAREZ, Mexico – This gritty metropolis just across the border from El Paso, Texas, lived through the most violent month in its history in August, with more than 300 people murdered in drug-related violence, Mexican media reported Tuesday.

So far this year, Juarez, considered Mexico’s most dangerous city and the scene of frequent shootouts between rival drug traffickers, has registered 1,457 murders, accounting for some 30 percent of the nearly 5,000 killings reported between January and August across Mexico.

A total of 302 people were murdered last month in the border city, according to some press tallies, with the daily Milenio putting the number at 326, well above the 253 killings reported in Juarez in all of 2006.

The murder rate took off in the border city of 1.5 million people in 2007, when more than 800 people were killed, then it more than doubled to 1,623 in 2008.

Mexican officials, who deployed 8,000 federal police and soldiers in the border metropolis months ago in an effort to reduce the violence, dealt some blows to organized crime groups in August, such as the arrests last weekend of four suspects in connection with 211 murders.

Most of the victims of the gunmen, who belonged to the “La Linea” gang, were involved in “the sale of drugs, extortion, kidnappings, vehicle theft and violent robberies of local businesses, according to information provided” by the suspects, the Joint Operation Chihuahua office said.

The huge security operation, however, has failed to prevent massacres such as the Aug. 18 attack on the Seven & Seven bar that left seven men and a woman dead, and four other people wounded.

The body of one of the five people murdered in the past few hours, a man who had been handcuffed and apparently tortured, was found at the bar at midnight.

A 20-year-old man was gunned down early Tuesday in Salvarcar, a neighborhood in the southern section of Juarez.

A few minutes later, a 31-year-old man was shot to death and his 38-year-old wife was seriously wounded in the same area.

Another couple was gunned down almost at the same time on a street in Morelos, a neighborhood in the southern part of Juarez.

The death toll has soared in the border city as gunmen working for rival drug cartels battle to gain control of the routes used for smuggling cocaine, marijuana, heroin and other drugs into the United States.

The Juarez drug cartel, with which the La Linea gang is allied, has been battling the Beltran Leyva and Sinaloa cartels for control of Juarez.

Chihuahua, where Juarez is located, was Mexico’s most violent state in 2008, with 2,206 murders reported. EFE