although (it is a certain time/condition)
Used to describe an action or event that happens during a specific time or condition, often with a sense of interruption or unexpectedness.
This pattern expresses that an action takes place at the very moment or state described by the preceding clause, and the main clause often involves an interruption, a request, or an unexpected event. It has a nuance of 'even though it was that time/condition' or 'while I was in the middle of...'. For example, 電話しているところを邪魔された means 'I was interrupted while I was on the phone.' The pattern is commonly used to apologize for bothering someone, to describe an interruption, or to note that something happened despite the timing being inconvenient.
It is a written and somewhat formal pattern. In daily conversation, you might hear it in set phrases like お休みのところをすみません (Sorry to bother you while you're resting), but it's more typical in announcements, news, or careful speech. The を can be followed by verbs like 邪魔する (to disturb), 見つかる (to be found), 呼び出す (to call out), etc., which indicate that the action happens while the state is ongoing.
Note that the meaning is not 'place' but 'time/occasion'. The noun ところ literally means 'place', but here it refers to a point in time. This can be confusing, but context makes it clear.