Riot police push away students, inside the University of Puerto Rico, in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
File Photo: Students and protestors clash at University of Puerto Rico in December over a new fee proposed by administrators. (AP)
A demonstrator yells at riot police officers as she is detained during a students protest outside the Capitol building in San Juan, Puerto Rico, Thursday, Jan. 27, 2011. Students have been on strike to demand university officials eliminate a new $800 yearly fee that went into effect in Jan. 2011. Students of Puerto Rico's University already pay a $49 fee per semester. (AP Photo/Ricardo Arduengo) (AP2011)
A student protester is detained by riot police at the University of Puerto Rico in San Juan, Puerto Rico, Wednesday Jan. 19, 2011. (AP2011)
Riot police stand in formation during a protest in front the Capitol building in San Juan, Puerto Rico, Thursday, Jan. 27, 2011. Students of Puerto Rico's University who already pay a $49 fee per semester, have been on strike to demand university officials eliminate a new $800 yearly fee that went into effect in Jan. 2011. (AP Photo/Ricardo Arduengo) (AP2011)
A demonstrator touches the shield of a riot police officer during a protest outside the Capitol building in San Juan, Puerto Rico, Thursday, Jan. 27, 2011. (AP Photo/Ricardo Arduengo) (AP2011)
A student protester is detained by riot police at the University of Puerto Rico in San Juan, Puerto Rico, Tuesday Jan. 25, 2011. Students are demanding university officials eliminate a new $800 yearly fee that went into effect at the beginning of the year. Students already pay $49 per credit. (AP Photo/Ricardo Arduengo) (AP2011)
A student protester is detained by riot police at the University of Puerto Rico in San Juan, Puerto Rico, Tuesday Jan. 25, 2011. (AP2011)
A student protester is detained by police at the University of Puerto Rico in San Juan, Puerto Rico, Tuesday Jan. 25, 2011. (AP2011)
A demonstrator shouts at riot police during a protest at the University of Puerto Rico in San Juan, Puerto Rico, Tuesday Jan. 25, 2011. (AP2011)
A demonstrator talks to a police officer after being detained during a protest in front the Capitol building in San Juan, Puerto Rico, Thursday, Jan. 27, 2011. (AP2011)
Police detain a demonstrator during a protest in front the Capitol building in San Juan, Puerto Rico, Thursday, Jan. 27, 2011. (AP2011)
Using shields, riot police push away a group of students at the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
Using shields, riot police push back a group of students, inside the University of Puerto Rico, in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
Riot police advance toward a group of students at the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
Surrounded by tear gas, riot police advance toward a group at the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
A university student protestor is detained as riot police advance toward a group of students inside the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
Plain clothes police officers donning bulletproof vests detain a student protestor at the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
A university student protestor is taken into custody outside the University of Puerto Rico in San Juan, Puerto Rico, Thursday Jan. 13, 2011. (AP2011)
Students march in front of the University of Puerto Rico in San Juan, Thursday Jan. 13, 2011. (AP2011)