Updated

Meth abuse continues to fuel an increase in crimes like robbery and assault, straining the workload of local police forces despite a drop in the number of meth lab seizures, according to a survey Tuesday.

Nearly half of county law enforcement officials consider methamphetamine their primary drug problem, more than cocaine, marijuana and heroin combined, the survey of the National Association of Counties found.

"Abuse of this highly addictive brain-altering drug continues to destroy lives and strain essential county services across America," said Bill Hansell, the association's president and commissioner of Umatilla County, Ore.

The survey of 500 county law enforcement officials in 44 states showed that about half reported a decrease in the number of meth lab busts as a result of laws that restrict the sale of cold medicines with precursor ingredients used in the manufacture of meth.

That's consistent with federal figures released last month showing a 30 percent drop in the number of labs seized nationwide. But county officials said supply of the drug remains high from superlabs in California and Mexico.

About half the counties reported that one in five inmates are jailed because of meth-related crimes like robberies and burglaries. Another 17 percent of counties reported that one in two inmates are incarcerated for meth-related activity.

Hansell called on Congress to develop a comprehensive strategy to deal with the meth problem that includes more funding for anti-drug task forces, drug prevention campaigns, treatment programs and cleanup of toxic chemicals used to make meth.

Last month, the White House drug-policy office set a goal to cut meth use by 15 percent over the next three years and increase seizures of meth labs by 25 percent.

Hansell also urged federal lawmakers to reject a Bush administration proposal to eliminate the Justice Assistance Grant program, which funds drug task forces around the country. That call was echoed by local law enforcement officials at a news conference to announce the survey.

"It makes absolutely no sense to fight a war on drugs, then reduce the funding when you're in the midst of battle," said Oklahoma County Sheriff John Wetsel. About 1,000 of the 2,800 inmates in the Oklahoma County jail are incarcerated for meth-related crimes, he said.

The survey, taken at the end of June, is based on a random sample of sheriffs or police chiefs in 500 of the nation's 3,066 counties. The association does not reveal the identity of the counties because it would discourage them from responding freely, said Jacqueline Byers, NACo's director of research.