Cryptic crossword No 4,006

Across

1. Push back, leper! Push back! (5)
2. A star? That's you in last place! (3)
3. Evildoer wrestled Mel for a cat (10)
4. Emergency room houses the chemical (5)
5. We took and redefined martial art (3,4,2)
6. Dynasties of Thailand reported measurements of duration (7)
7. Bottomless purse left in dirt with no right to surprise market (7)
8. Like a human (or a chimp), failing to contain destruction of Porto, New Hampshire (15)
9. I think pie mostly has onion crust (7)
10. Nuclear headswap, or something (7)
11. It's not S? (9)
12. Went away quickly in France (3)
13. Tea boy (i.e. Stefan C. Chest) sometimes led past governments (10)

Down

1. School is no longer making, uh, noises (6)
2. Redo brown Peru sash; the last two would fall rapidly (8)
3. Omar in Eritrea smuggles sailor (7)
4. Disastrously full? Be maced in a mobile medical facility! (5,9)
5. Adjudicator was told to sample Spooner's fresh bovine (8)
6. Writes down the best ones (7)
7. His only bad side: destroying edges with decorative patterns (6)
8. Contents of Sussex portacabin to be sold overseas (6)
9. Plant liquids required shifting soil (9,4)
10. A national theme having emblematic musical opening? (6)
11. Alf, reflecting, sat up: ”A breakfast food has no depth!“ (4,2,1,7)
12. Lost deed, confused, dethroned: woman in a state (5,8)