GARY | The Indiana Department of Transportation Wednesday morning announced the indefinite closure of the Martin Luther King Drive bridge over the Borman Expressway in Gary citing safety concerns.

INDOT officials said they believe cracks found on the concrete beams have compromised the load-bearing capacity of the bridge, a statement issued Wednesday said. The agency plans to replace the bridge beams and concrete "as soon as possible," the statement read.

Traffic is being rerouted to Broadway via 21st and 35th Avenues.

INDOT reports the bridge carried 4,100 vehicles daily.

The state hopes to select an engineering firm to begin construction this fall and reopen the bridge to traffic by June 2011. The project is expected to cost around $2.5 million.

The action comes after a Friday afternoon report from staff bridge engineers regarding the severity of the cracks on the concrete support beams and bridge deck. Traffic was retracted Saturday to passenger vehicles with special enforcement by Indiana State Police to keep trucks and buses off the bridge.

The bridge was built in 2004 to span the widened Borman Expressway.

"INDOT is looking at various aspects of the design and construction to understand why problems appeared in the bridge only six years after it was constructed," a news release issued Wednesday morning said.

Crews will be inspecting other bridges constructed during the same timeframe in the immediate area as a precautionary measure to ensure their integrity, INDOT said.

The MLK bridge closure comes on the heels of December's permanent closure of the Cline Avenue bridge due to structural safety concerns. INDOT plans to demolish the bridge by 2013 and this year will begin building a permanent detour along Dickey Road and Riley Road for the 35,000 vehicles that previously used the bridge daily.