Learn Turkish: Güneş doğana kadar isyancılar saklanmaya mecbur kaldı. - The rebels were forced to hide until the sun rose.

This follows the standard structure for being forced to do an action. You take the verb saklanmak (to hide), turn it into a short verbal noun with -ma, and add the dative case -ya because the adjective mecbur requires it. Literally, it means they were left obligated to hiding.

Could we say mecbur oldu instead of mecbur kaldı here?

Yes, but mecbur kalmak is the more natural choice for this specific context. While mecbur olmak generally means 'to be obliged', mecbur kalmak emphasizes being left with no other choice due to unfolding circumstances (situational compulsion), such as waiting out the sunrise.

Why use saklanmaya instead of just saklamaya?

The base verb saklamak means to hide something else (like a weapon or a secret). To express hiding oneself, Turkish adds the reflexive suffix -n to create saklanmak. Since the rebels are hiding themselves, we must use the reflexive form.

The English translation is in the past tense ('until the sun rose'). Why doesn't doğana kadar have a past tense suffix?