Shares in American Airlines (NASDAQ:AAL) were down 2.4 percent early Tuesday following terrorist attacks at Zaventem airport in Brussels that left at least 11 dead and many more wounded. Shares of Southwest Airlines (NYSE:LUV) fell 1.8 percent. 

According to early reports, one of the two suicide bombings occurred at the gate operated by American Airlines. But the airline has rebuffed those accounts, saying in a statement that the explosion did not take place at Row 8, where the American Airlines desk is. 


"American Airlines is taking care of our employees and customers in Brussels after this morning’s events. At this time, there are no reported injuries to our employees," the airline said. The air carrier canceled Flight 751 from Philadelphia to Brussels following news of the explosions. 

An hour after the airport attack, a third blast tore through Maelbeek metro station, which sits near the European Commission. That attack left at least 15 dead and 55 more injured. Markets in Belgium and throughout Europe tumbled Tuesday after the attacks. 

British travel operator Thomas Cook Group saw its stock drop 4.7 percent Tuesday to $125.78. Shares in Accor SA, the French hotel company, slid 4.6 percent to $41.74.

Shares in travel booking sites also fell early Tuesday. Priceline Group (NASDAQ:PCLN) was down 2.6 percent pre-market, and Expedia Inc. (NASDAQ:EXPE) fell 2.4 percent.