Mexico's prickly pear cactus, which is emblazoned on the country's flag, could soon play a new and innovative role in the production of biodegradable plastics.

The United States and Mexico reached an 11th-hour deal late Friday to crack down on migration from Central America, with President Donald Trump relenting on threats to slap potentially devastating tariffs on the neighboring country.

With Trump ready to impose five percent tariffs on all Mexican goods starting Monday, senior officials hammered out an agreement after three days of intense negotiations at the State Department.

A strong 6.2 magnitude earthquake struck off Mexico's Pacific coast on Tuesday, slightly shaking towns, but no immediate damage was reported, authorities said.

The quake struck at 1051 GMT in the ocean 105 kilometers (65 miles) southwest of the tourist resort of Manzanillo, and 641 kilometers (398 miles) west of Mexico City, the U.S. Geological Survey reported.

U.S. authorities have uncovered what they believe to be the longest ever cross-border drug trafficking tunnel connecting Mexico and California, a statement said.

Estimated to span more than 800 yards (730 meters), it contains an elevator, as well as lights and rail and ventilation systems, the U.S. Attorney's Office for the Southern District of California said Wednesday.

Donald Trump wants to force Mexico to pay for a giant wall along the southern U.S. border by threatening to cut off billions of dollars sent home by Mexican immigrants, a U.S. newspaper reported Tuesday.

The Republican frontrunner's promise to build the wall, in a bid to stop illegal immigration, and force Mexico to foot the estimated $8 billion bill is a cornerstone of his increasingly under fire campaign for the presidency.

U.S. President Barack Obama congratulated his Mexican counterpart Enrique Pena Nieto Friday on the recapture of drug baron Joaquin "El Chapo" Guzman, the White House said.

The kingpin's daring escape last year created a major embarrassment for the Mexican leader, who had balked at extraditing the druglord to the United States even though Guzman had already fled from another prison in 2001.

A meeting Tuesday in Mexico City of representatives from the United States, Central America and Mexico failed to make a breakthrough on the situation of thousands of Cuban migrants stranded in Costa Rica, the foreign minister of that country said.

"Unfortunately the Guatemalan position was unchanged" from last Friday, when a meeting of Central American nations refused Costa Rica's call to allow the U.S.-bound Cubans passage north, Foreign Minister Manuel Gonzalez told reporters.

Mexico has created a special unit to investigate the disappearance of 43 students last year, yielding to longstanding demands of irate parents who dismiss the government version of what happened.

Prosecutors say municipal police in the southern town of Iguala abducted the students and handed them over to a drug gang, which killed them and incinerated their bodies at a landfill in September last year.

Human rights violations against migrants in Mexico have surged since the government launched an operation last year to curb illegal crossings at the country's southern border, non-governmental organizations said Wednesday.

The Frontera Sur (Southern Border) operation was launched in 2014 to stop illegal crossing at the southern border with Guatemala following a surge of unaccompanied migrant children arriving in the United States.

Mexican authorities have searched several homes in three states and seized 11 small airplanes in their hunt for fugitive drug kingpin Joaquin "El Chapo" Guzman, prosecutors said Tuesday.

The attorney general's office said several properties were searched in Guzman's home state of Sinaloa in the northwest as well as the central states of Mexico and Puebla.