Islamabad, Pakistan, Muharram 16, 1433, Dec 11, 2011, SPA - Pakistan, in a bid to bolster its western border, has installed anti-aircraft guns and radars to monitor air activity, a senior Pakistani military official told CNN. "We had to do it after being deceived by our so-called friends," said the official, who spoke on the condition of anonymity. The move comes in response to a NATO airstrike last month that killed 24 Pakistani soldiers. The official declined to say how many anti-aircraft guns and radars were installed along the country's western border. --SPA 14:31 LOCAL TIME 11:31 GMT www.spa.gov.sa/951347