(CNN) -- The University of Texas at Brownsville was on alert Monday, as students, faculty, and staff return to campus, just days after gunfire along the U.S.- Mexican border cancelled classes, according to campus police.
"We will have the personnel out there in the field to monitor the situation south of the river," said John Cardoza, who told CNN Sunday that officials are constantly monitoring the violence in Mexico that's spilling over into U.S. cities along the border.
UTB's campus was evacuated Friday, and classes and activities were cancelled over the weekend, after a gunbattle in Matamoros, Mexico that left a suspected drug cartel leader dead.
According to a statement released by the Mexican Navy, "the series of gun battles" killed at least 55 people, including three marines, and a local reporter.
Campus police chief Cardoza disputed media reports that stray bullets hit some vehicles and buildings on campus, and said his department acted quickly to protect students with the help of federal, state and local police.
"They were already on site, ready to assist us in evacuating students," said Cardoza, who added that some officials remained on campus overnight to help make sure the campus was "secure and safe."
Despite concern from parents, one student at UTB told CNN Sunday, that he feels safe coming back to campus, and he didn't know any students not planning to return.
"I think the university has set a lot of precautions and procedures in place to make sure that we feel safe," said Adam Cardoza, a sophomore at the school.
The University of Texas serves more than 12,000 students at its campus located in Brownsville, and is just minutes from international bridge crossings into Matamoros, Mexico.
The school's website encourages the campus community to be "aware of their surroundings," and to report any suspicious activity.