this plant just blew up. >> it's the isom, the isom! >> narrator: it was the biggest industrial accident in decades. >> get me at least a half dozen available firemen. we got people trapped in these trailers, trying to get to them. >> it's been a sad day for the bp texas city titans. it's a really sad day for me, personally, as well. at this time, regretfully and with shock, i have to report to you that there have been some fatalities. >> mr. browne has spent the morning visiting our site. he's now agreed to spend a few minutes with you. this is john browne, our group chief executive. >> thank you. ladies and gentlemen, good morning and thank you for joining us. yesterday was a dark day in bp's history. all of us at bp are very deeply saddened by the loss of life and injuries suffered by so many people. >> narrator: lawsuits ensued. >> my name is john manzoni. i live in london and i'm with bp and my... >> narrator: in a taped deposition, john manzoni, head of refining, was asked about his visits to texas city. >> when was the first time

there isome pulp within the tooth that will yield dna material. >> reporter: forsic pathologist wex'sults usually only take a few days and could answer the question to what happened to natalee. that is the gold standard. the nuclear dna analysis will tell you specifically and unequivocally without any question whatsoever whether it is that individual. >> reporter: authorities say joran van der sloot was the last person to see holloway alive. but the prime suspect in this case is in jail in ru. van der sloot is accused of murdering a 21-year-old peruvian woman back in may, nearly five years to the day natalee disappeare beth holloway's attorney spoke to matt lauer in june. >> it's no secret that he holds the key to where natalee is and at happened to her. we've always known that. >> reporter: the search for natalee holloway has been filled with dramatic twists and turns. soon, a mother may finally start to understand what happened to her daughter. for "today," tom trung, nbc news. >> we're back after these messages. r. - you went to kay. she' love it. [chuckles] trust me. i know. ho-ho