Search called off for 2 of 3 prison escapees, officials say

(CNN) - The search for two of three inmates who escaped from an Indiana prison has been called off, authorities said Tuesday.

One of the inmates, 48-year-old Charles Smith, was captured Monday. The other two - a convicted murderer and a convicted rapist - remain at large after Sunday's escape from the Indiana State Prison in Michigan City, Indiana.

The Indiana State Police called off the formal search for them because no sign of the men had been found, Indiana Department of Correction spokesman John Schrader told CNN Tuesday. He said the search was ended Monday evening.

The inmates apparently escaped through underground tunnels beneath the prison, and authorities are still trying to determine how they gained access to them.