Republican presidential hopeful John McCain waves to photographers upon arrival in Mexico City, 02 Jul 2008

U.S. Republican presidential candidate John McCain is in Mexico to hold talks with Mexican President Felipe Calderon.

McCain arrived in Mexico City late Wednesday from Colombia, hours after Colombian military forces pulled a daring mission to rescue 15 hostages from leftist FARC guerillas, including French-Colombian politician Ingrid Betancourt and three U.S. military contractors.

The presumptive Republican nominee released a statement saying Colombian President Felipe Uribe informed him about the planned operation during their meeting Tuesday evening.

He says he learned learned of the success of the mission while speaking with Mr. Uribe on his flight to Mexico Wednesday.

McCain's Democratic rival, Barack Obama, praised the hostage rescue operation.

On Wednesday, McCain said the continuing flow of drugs from Colombia through Mexico into the United States is a major challenge for all Americans.

Some information for this report was provided by AFP and Reuters.