Concerned Colombians flooded a plaza in historic Cartagena, after news that the city's newly elected mayor had been diagnosed with lung cancer.

The bad news came as the nation's president, Juan Manuel Santos, recovered from prostate cancer surgery and the vice president deals with the effects of a serious stroke.

During the four-hour weekend rally, city officials joined pastors and worshippers to pray for the health of their leaders and the well-being of their country.

"We're obeying the biblical mandate that says we should pray for all the authorities," Pastor Jaime Ospino, with Pastors Association, said.

"And knowing the health condition of Mayor Campo Teheran, and also the president and the vice president, the churches of Cartagena felt we should have special prayer for our authorities," he said.

Days after attending the prayer event, Vice President Angelino Garzón announced his resignation to battle yet another health threat, prostate cancer. 

Church leaders are already discussing the need for more united prayer rallies in the days ahead.