Unclued lights make up a group, its members and location (two pairs, one doubly hyphened). Ignore one accent

Across

1    Red Route heartless? Tough (5)

4    Hugo’s girl’s medals are amazing (9)

11    Possible political pact on the left, I spill the beans (3-3)

12    From the outside, edged in to brush chamber (7)

15    Irritating, but not spiteful at first (5)

16    Violently purges sporting competition (5,1)

22    Voles, millions perishing in frozen expanse (5,3)

25    Rank covered in the Tatler (4)

27    Dutchman confuses me with Henry (7)

29    Amateur not fully taught to employ unknown weedkiller (8)

34    Miles for couple to cross high range (5)