MONROVIA, Liberia (AP) — Liberian law enforcement agents burned some 4.2 metric tons of cocaine worth about $336 million on Thursday, days after authorities announced the country’s largest-ever drug seizure and implicated senior police officials in the trafficking operation.Authorities said investigators identified officers who had allegedly helped escort the cocaine after it arrived in Liberia. The police chief of highway patrol and the head of major crimes have been charged, while a deputy police commander at the country’s main airport is also a suspect, Police Inspector General Gregory O.W. Coleman said.Liberian authorities said last week they seized nearly 4 metric tons (8,818 pounds) of cocaine with an estimated “street value” of around $317 million, and detained two foreign nationals while investigating what they described as a sophisticated transnational trafficking network. They called it the biggest drug bust in the country’s history.

The Justice Ministry said investigators recovered the cocaine during a raid at a property in Duazon, about 28 kilometers (17 miles) from the capital, Monrovia. A Serbian national and a dual Colombian-Spanish national were arrested and were being questioned, it said.Liberia’s police and drug enforcement agency also burned 237 kilograms (522 pounds) of cocaine valued at more than $19 million that was seized in June at Roberts International Airport.