FILE - In this Wednesday, Aug. 28, 2013 file citizen journalism image provided by the United media office of Arbeen which has been authenticated based on its contents and other AP reporting, a member of a UN investigation team takes samples of sands near a part of a missile is likely to be one of the chemical rockets according to activists, in the Damascus countryside of Ain Terma, Syria. The intelligence linking the Syrian regime and President Bashar Assad to the alleged chemical weapons attack that killed at least 100 Syrians is no “slam dunk,” with questions remaining about who actually controls some of Syria's chemical weapons stores and doubts about whether Assad himself ordered the strike, U.S. intelligence officials say. (AP Photo/United Media Office of Arbeen, File)

What is the Chemical Weapons Convention?

UNITED NATIONS (AP) — Syria took the first step Thursday toward joining the Chemical Weapons Convention after its most important ally, Russi…

U.S. Secretary of State John Kerry, centre, on arrival at Cointrin Airport, in Geneva, Thursday, Sept. 12, 2013, prior to his meeting with Russian Foreign Minister Sergey Lavrov to discuss the ongoing problems in Syria. (AP Photo/Larry Downing, Pool)

Kerry set to test Russia on Syria weapons

GENEVA (AP) — U.S. Secretary of State John Kerry and his team open two days of meetings with their Russian counterparts on Thursday, hoping …

President Barack Obama addresses the nation in a live televised speech from the East Room of the White House in Washington, Tuesday, Sept. 10, 2013. President Obama blended the threat of military action with the hope of a diplomatic solution as he works to strip Syria of its chemical weapons. (AP Photo/Evan Vucci, Pool)

Obama conditionally backs offer on Syria

President Barack Obama conditionally endorsed a Russian offer for international inspectors to seize and destroy deadly chemical weapons in S…