tight-lipped

To avoid making the batteries a target, Ukrainians are tight-lipped about their specific location and details of the measures in place to protect them from Russian attack, which include strategically placed air defenses.

They're tight-lipped, however, about larger career goals.

Tung has been tight-lipped about his ascent to the country’s busiest circuit.

Authorities have been tight-lipped about what role - if any - the suspect's politics played in the attack.

In the small town of Korumburra though, where the Wilkinson and Patterson families are firmly rooted, the community has closed ranks around them, and remained tight-lipped during the media onslaught.