Honduran authorities have arrested four people in connection with the murder of environmental activist Berta Caceres, including three who worked for a hydroelectric project she opposed.

Public prosecutor's office spokesman Yuri Mora says those arrested worked for or were employees of Desarrollos Energeticos SA, which was developing the project that Caceres' organization successfully fought.

The Goldman Environmental Prize-winning activist was shot dead March 3 by gunmen who invaded her home. Caceres had reported death threats from security personnel for the company known as DESA.

DESA did not immediately respond to a request for comment on Monday's arrests. In the past it has denied involvement in Caceres' killing.

Mora identified those arrested as Douglas Geovanny Bustillo, Mariano Diaz Chavez, Sergio Rodriguez Orellana and Edilson Duarte Meza