Federal agents were carrying out an operation Tuesday at a municipal office building in San Juan, Puerto Rico, Telemundo PR reported.

FBI agents were seen raiding an office on the 15th and 14th floor of Torre Municipal de San Juan, according to authorities. The operation was related to suspected corruption in the purchasing department.

Allegations made by a former employee point to a pattern of favoritism with a company that has bid for projects with the city, El Nuevo Día reported.

"We are seeking documents and evidence that support this allegation," FBI spokesman Carlos Osorio said. "This search will help us confirm if allegations are true or not. We will look through every document, bill, email...anything that will let us clarify the claims."

The raid has required a number of FBI agents who have occupied several floors of the building, he said. Osorio said this is the first time the FBI has raided the building, El Nuevo Día reported.

San Juan Mayor Carmen Yulín Cruz said on Twitter that her instruction "is always total collaboration."

"If someone has done something wrong, they should be subjected to due process and face the consequences of their actions," she said.