The Foreign Ministry on Thursday advised Chinese citizens planning to travel to the United States to exercise caution over entry-related risks, citing a recent incident in which about 20 Chinese scholars were questioned and denied entry at Seattle-Tacoma International Airport.

The scholars, who held valid visas and were traveling to attend an academic conference in the US, were subjected to unreasonable questioning and harassment by US Customs and Border Protection officers, according to the ministry.

The ministry and Chinese diplomatic missions in the US reminded those planning near-term trips to strengthen safety awareness, familiarize themselves with US entry rules and make adequate preparations before departure.

In addition, it advised travelers to avoid entering the US through the Seattle airport if possible. Those questioned by US law enforcement officers should stay calm and handle the situation rationally, the ministry said.