Police superintendent Jose Figueroa Sancha met Monday with his regional commanders after another weekend of violence left 16 dead in Puerto Rico.

The conference followed an admission by the force's head of field operations, Col. Leovigildo Vazquez, that the murder rate has resumed rising this month after remaining stable in April.

The 16 homicides over the weekend bring to 405 the number of murders registered in Puerto Rico so far this year, compared with 315 during the same period of 2010. The latest victim is 18-year-old Bryan Hernandez, fatally shot Sunday night in San Juan's Santurce neighborhood.

Authorities are especially concerned about a surge in multiple-homicides.

Crime, most of it associated with battles between rival gangs over control of drug corners, has emerged as Puerto Rico's most serious social problem and is feared to post a threat to the island's vital tourism industry.