* TCO reports an incident at Tengiz on March 11; no

injuries

* Field has not halted output, sources say

* Tengiz was already pumping lower levels after January

18 fires

* Recovery limited by CPC loading constraints

(Combines reports, adds detail throughout)

ALMATY, March 13 (Reuters) - Kazakhstan's Tengizchevroil

consortium said on Friday it was checking the cause of a March

11 "incident" at the country's largest oilfield of Tengiz that

caused no injuries, while sources said the field had not stopped

production.

The oilfield at the northeastern tip of the Caspian Sea had

been pumping oil at lower levels after fires at power stations

on January 18, boosting uncertainty on global markets battling

constricted supplies because of the US-Israel war on Iran.

"The company is assessing the root cause in line with

established processes," said TCO, operated by the U.S. oil major

Chevron ( CVX ), as it confirmed the incident at one of its

facilities at Tengiz, and added that there were no injuries.

"Beyond this, TCO does not comment on specific details of

its operations," it said in a statement.

Oil output at Tengiz rose to 810,000 barrels on March 11,

but had averaged 495,000 barrels per day (bpd) over the first 10

days of this month, lagging the capacity target, two industry

sources said on Thursday, speaking on condition of anonymity.

Output recovery at Tengiz is capped by loading constraints

such as adverse weather and the threat of drone attacks on the

main export route, the Caspian Pipeline Consortium (CPC) system.

Oil production at the Tengiz field had recovered to 120,000

tons per day, or the equivalent of 955,000 bpd, Kazakhstan's

Energy Minister Erlan Akkenzhenov told reporters on Wednesday.