OptionMonster co-founder Pete Najarian provides options picks Monday, Wednesday and Friday in TheStreet.com's Deep in the Money Calls newsletter.

Mike Yamamoto, managing editor of OptionMonster.

Bearish traders apparently see weakness ahead for emerging markets and are buying downside options in a key exchange traded fund expected to decline in the next two months.

Almost all of today's options trading in the Claymore/BNY Mellon BRIC ETF ( EEB) took place at the September 33 contracts, where more than 7,000 puts were bought in the first hour of trading alone. The bulk of those trades came in just two blocks of 4,500 and 2,250 within one second of each other for $1.20, according to OptionMonster's real-time tracking systems.

Total trading volume for all puts and calls average just 203 a day in the emerging market ETF. Today's activity dwarfed the open interest of just 67 contracts and the average put turnover of only 4 contracts at the September 33 strike.

The ETF is off 0.7% to $34.81 in midday trading, but it has risen some 80% since the beginning of March and is nearly double its 52-week low of $17.60 from November. The shares would need to drop at least another 8.5% by the Sept. 18 options expiration for most of the puts purchased today to turn a profit.

Traders may be wagering that emerging markets are topping out after their blistering run since the spring. Research firm EPFR Global said today that the sector drew $2.6 billion in the week that ended Wednesday, the most inflows into emerging markets in more than a month.