Nightly news begins right now. From nbc news World Headquarters in new york, this is nbc nightly news. Reporting tonight lester holt. Good evening. Is it safe to go there . Against the spector of terrorism its a question so many ask before venturing off on overseas vacations these days. Sadly for dozens of tourists who are about to visit one of the important museums of the arab world, the answer proved no, at least for today. In tunis, tunisias mediterranean capital, armed gunmen opened fire. They killed at least 19 people and wounded around 50. Most of them vacationers from europe. Many had just arrived on cruise ships. Nbcs katy tur has been working this story for us all day and has more. Reporter guns drawn, tunisian officers scramble to evacuate tourists from the museum. One describes her terror as police told her to get out fast saying, you must run, you must run. The gunmen killed at least 19 people. Others were held hostage. Tunisian forces finally killed two gunmen, but others