(CNN) Iranian missiles that targeted eastern Syria early Monday came within three miles of US troops in the country, a US defense official told CNN.

into the Al Bukamal district in Syria. State media citing Iran's Revolutionary Guard Corps (IRGC) said the attack targeted militants allegedly involved Iran launched six ballistic missilesinto the Al Bukamal district in Syria. State media citing Iran's Revolutionary Guard Corps (IRGC) said the attack targeted militants allegedly involved in the September 22 attack on a military parade in the southwestern city of Ahvaz

US satellite surveillance last week had shown mobile missile launchers were moving into positions in Iran where missiles were fired from, the official said. The US is closely watching those launchers and any potential movement, the official added.

The missiles were launched from Kemansheh, Iran -- seven military drones also fired missiles into eastern Syria, according to a report in the official Islamic Republic News Agency (IRNA) citing an IRGC statement.

The missiles had "death to America," "death to Israel" and "death to the house of Saud" written on them, according to Fars News, which also released video showing the launching of the missiles.

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