Mexican prosecutors have said the main suspect a brazen daylight shooting of a US consular official is an American citizen. The unnamed man will be deported to the United States, officials said.
Mexican authorities announced the shooting suspect's arrest on Saturday, saying the unnamed man would face justice in the United States for the "sordid and cowardly" attack.
The federal Attorney General's Office said that "a U.S. citizen was identified and detained for his presumed involvement in the case. This person will be deported to the United States, to determine his legal situation."
The US consular official who was shot remains hospitalized in stable condition, the office said.
The shooting victim's identity has not been released and authorities have not commented on a possible motive for the attack. A source told Reuters news agency that the official was shot in the chest.
US Secretary of State John Kerry issued a statement thanking Mexico for quickly apprehending the suspect.
"On behalf of President Obama and the people of the United States, I want to thank the Government of Mexico for their swift and decisive arrest of a suspect in the heinous attack against our Foreign Service Officer colleague," Kerry said.
"My thoughts and prayers remain with this officer and his family during this difficult time. I wish him a speedy recovery."
The FBI had previously offered a $20,000 reward for information about the shooter's identity.
Guadalajara and the rest of Mexico's Jalisco state have been hit by violence enacted by the powerful Jalisco New Generation drug cartel in recent years.
US consular employees and other US agents have been attacked in Mexico in the past in attacks the assailants claimed were cases of mistaken identity.
rs/kl (AP, AFP, Reuters)