A woman was killed after she braked her minivan at the entrance to the I-495 Express Lanes in Fairfax County Tuesday afternoon, authorities said.



She has been identified as Mary Jane Treacy, 72, of Bluffton, S.C.



Virginia State Police say Treacy braked her Chrysler Town and Country minivan at the entrance to the northbound Express Lanes near mile marker 54. The driver of a Jeep Wrangler was able to swerve to avoid a collision, but a Mercedes sedan couldn't stop in time and rear-ended the minivan.



The impact caused the Mercedes to spin around and hit the Jeep before catching fire. The driver of the Mercedes, a 30-year-old Dulles man, was able to escape the burning car.



Virginia State Police were called to the scene around 3:45 p.m.

Treacy and her husband, Thomas M. Treacy, 78, were transported to Fairfax Inova Hospital, where she died a short time later. Her husband's injuries were described as serious but not life-threatening.



The drivers of the Mercedes and the Jeep were transported to Fairfax Inova Hospital and are expected to be OK.



Authorities are continuing to investigate the crash. No charges have been filed.



The Express Lanes on I-495 in Virginia opened in November 2012, and the changes to I-495 initially confused some drivers. Six collisions were reported within the first three days.

In response, project leaders added better road markers, and extended both dotted and solid lines on the roadway to alert drivers to the differences between the regular I-495 lanes, and the Express Lanes, which require an E-ZPass.

All six of those early crashes occurred at the entrance to the northbound Express Lanes at the Braddock Road exit, the same interchange where Tuesday's fatal crash occurred.

In June 2013, the speed limit on the Express Lanes was increased to 65 mph.



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