* Whitehaven Coal second biggest pct loser on ASX

* Biggest gas pipeline operator APA Group down 4%

* NZ bourse operator says hit by cyberattack

Aug 26 (Reuters) - Australian shares fell 1% on Wednesday in a broad-based sell-off as the state at the centre of a second wave of coronavirus cases in the country recorded its second deadliest day of the pandemic.

Victoria, the country's second-most populous state, saw 24 deaths on Wednesday, compared with the record 25 reported last week.

The S&P/ASX 200 index slipped 64.40 points to 6,097 by 0102 GMT and was on track to snap two straight sessions of gains, with investors also spooked by the Victoria government's intention to extend a state of emergency by another year to combat the spread of the virus.

Investors shrugged off optimism around U.S.-Sino trade negotiations and fresh progress in the medical battle against COVID-19 that helped lift Wall Street indexes to record highs overnight.

Financials stocks led the retreat with a drop of nearly 2%. Australia and New Zealand Bank and National Australia Bank shed 2.3% and 2.1%, respectively.

APA Group fell 4.1% as the country's biggest gas pipeline operator forecast a weaker fiscal 2021, while Whitehaven Coal slid more than 9% to its lowest in over four years after the country's largest independent coal producer reported a 95% plunge in full-year underlying profit.

Technology stocks slipped up to 1.4% and were on track to snap a six-session winning streak.

Zip Co Ltd climbed more than 18% to an all-time high after the buy-now-pay-later firm partnered with eBay Inc to offer flexible credit to small- and medium-sized businesses.

In New Zealand, the benchmark S&P/NZX 50 index slipped 0.2%, or 22.5 points, to 11,970.6 after three consecutive sessions of gains.

Bourse operator NZX Ltd said it was likely hit by a second cyberattack in as many days on Wednesday, as trading in its cash markets was suspended at 2324 GMT. (Reporting by A K Pranav in Bengaluru; Editing by Subhranshu Sahu)