Al Qaeda leader warns of 'gravest consequences' if Boston marathon bomber executed

CAIRO (Reuters) - Al Qaeda leader Ayman al-Zawahri warned the United States of the "gravest consequences" if Boston marathon bomber Dzhokhar Tsarnaev or any other Muslim prisoners is executed.

from Reuters: Top News http://uk.reuters.com/article/uk-usa-boston-qaeda-idUKKCN0ZH4TD?feedType=RSS&feedName=topNews