Kabul, Afghanistan (CNN) -- Afghan President Hamid Karzai condemned a suicide bombing Monday at a military airfield, the latest incident in a spike in violence after the burning of Qurans by NATO troops last week. At least nine people were killed and 12 wounded in the early-morning explosion near the front gate of the NATO-led International Security Assistance Force base at Jalalabad airport in eastern Afghanistan, according to Gen. Abdulla Hazim Stanikzai, the provincial police chief. There were no NATO casualties. The Taliban insurgency said the attack was in retaliation for the Quran burning and said it hoped the attacks will continue "with the anger of the public."
@highlight
A suicide bomber targeted a NATO base, an official says
@highlight
At least 9 people are killed and 12 wounded in the explosion, the official says
@highlight
Another attack of "some significance" reported near Pakistani border
@highlight
Food at a NATO base appears to have been contaminated, ISAF says
"Yes, tension is high here in @placeholder right now, but across the country at large, the mission continues, and we're seeing the protest activity decline."