A young man paced back and forth at an intersection in one of San Juan's public housing complexes, Nemesio Canales. Suddenly, his head sprung up and a loud whistle echoed across the block, over the sound of roosters crowing.

'That's the sound the lookouts make when they see cops,' said Lt. Ferdinand Acosta of the San Juan Police Department. Drug smuggling has normalized lookouts in public housing projects in San Juan.

The situation in Nemesio Canales was so violent in the 90s they had guard shackles installed at its entrance. Although in the last couple of decades it has seen a decrease in criminality, many other neighborhoods in Puerto Rico's capital and other areas around the island have recently been the backdrop for innumerable homicides.

The first four months of 2018 in Puerto Rico, as of April 29, have seen 227 murders, 14 more compared to the same period last year, and of these, more than 90 are related to drug violence. But those who would fight crime are leaving the force. In just five years Puerto Rico lost nearly a quarter of its police force. Out of those 17,000 officers, more than 4,000 have left their jobs. Many officers who have stayed on the force are unhappy with what they say are low salaries and meager benefits.

Meanwhile, crime is spiking on the storm battered island.

'We do have a problem with drugs, nearly 50 percent of the murders in Puerto Rico are drug related,' said Lt. Acosta.

On the 8th of April three men were gunned down in Manatí, a town 24 miles west of San Juan. One of them, Manuel Pizarro, was on federal probation in Florida and had been in Puerto Rico for eight months since getting out of jail.

'The area of the incident is a known drug point, and from what we know in the investigation we think Pizarro came to reclaim his territory,' explained Lt. Acosta. 'That incited into a drug war, with the result of him being killed with two other guys.'

This multiple murder is one of the five on the island since the beginning of the year. Last year's multiple murder count was five, in the span of 12 months.

'It's an indicator of the increase in violence in the country,' said Lina M. Torres Rivera, criminologist and professor at Sagrado Corazón University. 'The trend has been an increase in murders in metropolitan areas such as San Juan, followed by Caguas and the southern area of Ponce.'

According to the Secretary of Puerto Rico's Department of Public Safety (DPS), it's difficult to prevent these types of murders and a higher police presence on the streets wouldn't make a great difference.

'Is it fair to say that more police presence would prevent murders? No,' said Hector Pesquera, Secretary of the DPS. 'When we had 17,000 officers in 2012 there were 1600 murders that year. It's got nothing to do with it.'

Torres Rivera said even though criminal policy isn't only a matter for the police, the demoralization of the police officers exacerbates the situation.

'You spend time working, you risk your life a couple of times every day and the government doesn't even say thank you for your service,' said Edward Atanacio, a police officer in San Juan. 'I have nearly 20 years of service, and I'm very depressed, very frustrated. My partners are very upset, like me.'

For the rest of the story, please visit the Center for Investigative Journalism.

*This story is part of a special project in collaboration with students of the Arthur L. Carter Journalism Institute of the New York University (NYU).