killing 35-year-old katelyn clavette as she drove through the o'neill tunnel governor baker. >> our hearts and thoughts go out to the family that through an incredibly bizarre event lost someone today. >> reporter: state transportation crews spent the day checking more than 500 other openings on the state highway system within boston city limits. making sure they are secure.

killing 35-year-old katelyn clavette as she drove through the o'neill tunnel governor baker. >> our hearts and thoughts go out to the family that through an incredibly bizarre event lost someone today. >> reporter: state transportation crews spent the day checking more than 500 other openings on the state highway system within boston city limits. making sure they are secure. morning as clavette headed southbound. police say the cover labeled boston drain came from a hole just at the tunnel exit. after it hit, the car continued out into the left lane of the expressway. eventually hitting a wall along the shoulder. we spoke with terry granahan who was in the rush hour traffic. >> the the state police were blocking us so no one would hit the manhole cover and there's steel i imagine if it hit the car it would have hate person it would do some serious damage. >> reporter: of course there are surveillance cameras all along the expressway and people are going through the footage particularly before this incident look for anything that might point to why that cover was not secured on the hole. in