No 10667, Thursday 10 Jan 13, Sankalak

 This rounds off another excellent round from Sankalak.

ACROSS

1   Breaking ice, calm cop reveals the collaborator (10) ACCOMPLICE*

7   Support born royal, a conservative at heart (4) BACK {B}{A}{C}{K}

9   Precipitated calcium utilised (6) CAUSED {CA}{USED}

10 Baby’s dummy, source of comfort (8) PACIFIER [CD]

11 Portable mattresses are funny, carried by engineers (8) BEDROLLS {BE{DROLL}S}

12 End of affair after devious guile is more unpleasant (6) UGLIER {GUILE*}{R}

13 Time spent in the can (7) STRETCH [CD]

16 Amusing chap, one with a suggestion of constriction of the heart (7) CARDIAC {CARD}{I}{A}{C}

17 Make advance arrangements for large, new paper perhaps (3-4) PRE-PLAN {L+N+PAPER}*

19 They assist fighters for a short time (7) SECONDS [DD]

22 Acquire, say, motor, black it gives the baker a rise (6) BICARB (~buy){BI}{CAR}{B}

23 Mathematical statement on a quiet work out (8) EQUATION {A+QUIET+ON}*

26 A home for the priest to mature (8) VICARAGE {VICAR}{AGE}

27 Pull out an expert beginning to overreach in Delhi, say (6) UPROOT {U{PRO}{O}T}

28 Shaping tool for some mad zealots (4) ADZE [T]

29 Exercise for the char, close to exhaustion? Short nap is included (5,5) DAILY DOZEN {DAILY} {DOZE}{N}

DOWN

2   A bird to lift heavy weights (5) CRANE [DD]

3   Watch the alumnus wait at table (7) OBSERVE {OB}{SERVE}

4   Operated by foot, it covers daughter with a ringing sound (5) PEDAL {PE{D}AL}

5   A tax on one thousand letters (6) IMPOST {I}{M}{POST}

6   Hearten leaders of eastern nations with boldness (9) ENCOURAGE {E}{N}{COURAGE}

7   Bewildered bachelor ran away with key (7) BAFFLED {BA}{F}{FLED}

8   The city to split, you say? Come down to earth! (9) CLEVELAND (~cleave){CLEVE}{LAND}

14 Scared to death, tried fire treatment (9) TERRIFIED*

15 Applaud the directors for providing material to cover walls (9) CLAPBOARD {CLAP}{BOARD}

18 Pacify with a meal containing bits of carrots and artichoke (7) PLACATE {PLA{C}{A}TE}

20 Oration misinterpreted in Canada (7) ONTARIO*

21 The old people beginning to interact with one from Sanaa, perhaps (6) YEMENI {YE}{MEN}{I}

24 A deadly sin, for all to see, in American railway (5) USURY {US}{U}{RY}

25 Gas much in the news, one enveloping animal complex, reduced (5) OZONE {O{ZOo}NE}

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