By Paul Kiernan Of DOW JONES NEWSWIRES MEXICO CITY -(Dow Jones)- Mexican airport operator Grupo Aeroportuario del Pacifico SAB (PAC, GAP.MX), or GAP, said Wednesday that passenger traffic at its 12 airports rose 12% in June from a year ago, to 1.65 million. Domestic traffic increased 8.1% to 1.1 million passengers, while international traffic jumped 22% to 549,200 passengers, GAP said in a filing with the Mexican Stock Exchange. The company noted that effects of the local A/H1N1 influenza outbreak lingered in June 2009, giving last month's numbers an easier comparison. Overall traffic at GAP's top airport, in the city of Guadalajara, rose 20% in June to 596,600 passengers. During June, Alaska Air Group Inc.'s (ALK) Alaska Airlines opened a route between San Diego and GAP's airport in the Pacific tourist destination of Puerto Vallarta. Local budget carrier VivaAerobus began operating a route between Guadalajara and Mazatlan, operated by rival Grupo Aeroportuario del Centro Norte SAB (OMAB, OMA.MX). GAP's total passenger traffic rose 6.2% in the first half of 2010 from a year ago, to 10.24 million. The company's locally traded B shares were recently up 1.5% at 38.05 pesos ($2.95). -By Paul Kiernan, Dow Jones Newswires; 5255-5980-5178; paul.kiernan@dowjones.com