(MSNBC) — The number of methamphetamine “super labs” seized by Mexican authorities has rocketed in the last five years but shipments of the drug across the border have also continued to grow, according to government statistics.

The increase highlights how Mexico’s cartels have diversified beyond their traditional focus of exporting cocaine, heroin and marijuana by transforming their operations to also make methamphetamines on an industrial scale.

The U.S. Drug Enforcement Administration (DEA) has noted “a sustained upward trend in Mexican methamphetamine availability in U.S. markets.” Research by the U.S. government also shows that methamphetamine prices are falling and that the purity level of seizures is rising.

Note: Read our discussion guidelines before commenting.