UNITED NATIONS - Two teams of investigators from the global chemical weapons watchdog are due to arrive in Syria on Thursday and Friday to look into an alleged deadly attack in the Syrian town of Douma, Syrian U.N. Ambassador Bashar Ja'afari told reporters."These two groups will arrive separately to Syria on Thursday, today, as well as tomorrow on Friday," he said. "We're ready to escort them to where they want, whenever they want, anytime they want.""The OPCW (Organisation for the Prohibition of Chemical Weapons) sent four passports to the Syrian embassy in Brussels. The visas were granted immediately," said Ja'afari, adding that Syria was also prepared to grant visas for inspectors at the Syrian border with Lebanon.The OPCW has not confirmed the travel plans for the investigators.