Aircraft at the Syrian Shayrat Air Base are seen in this still image taken from undated handout video.

Aircraft at the Syrian Shayrat Air Base are seen in this still image taken from undated handout video.

Aircraft at the Syrian Shayrat Air Base are seen in this still image taken from undated handout video. Russian Defence Ministry/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. EDITORIAL USE ONLY. NO RESALES. NO ARCHIVE.

April 9, 2017 6:13 PM (UTC+8)