At least 6 dead after Colombia tourist boat capsizes

At least 6 people died when a boat carrying more than 150 passengers capsized while on a sightseeing tour on a reservoir in northwestern Colombia.

Colombian president Juan Manuel Santos visited the El Peñol-Guatapé reservoir, about 40 miles east of the city of Medellin, and promised authorities would do "everything in their power" to rescue any survivors and promised that searches would continue through the night.

Colombia's national disaster agency reported that 133 people were rescued, 16 were missing and 6 had died on Sunday evening.

"Rescue operations will continue as long as the weather conditions allow. There are 25 well-equipped rescue experts working," said the agency's director, Carlos Iván Márquez Pérez.

ABC News' Joshua Hoyos contributed to this report