The US embassy in Saudi Arabia has told US citizens in the kingdom and elsewhere in the Middle East to "exercise heightened vigilance", Khaleej Times reports.
The notice cites Houthi hostilities against Saudi Arabia and Iranian efforts to target US government officials. It warns that the hostilities could escalate rapidly beyond the immediate area.
The embassy describes "Iranian-supported Houthis" carrying out attacks on civilian airports and critical infrastructure. It says these caused civilian casualties and severe travel disruption. The notice does not refer to a specific attack. The Saudi-led coalition said there were no casualties or damage from Tuesday's interceptions near Riyadh, which it attributed to the Houthis.
The warning follows those interceptions of a ballistic missile and a cruise missile.
Khaleej Times also reports that India's IndiGo has extended its flight suspensions to Saudi Arabia. Flights to Jeddah and Madinah are suspended until 21 November, and flights to Riyadh and Dammam until 30 November.