Bundled securities tracking overseas markets suffered some of the steepest declines of Thursday's session, after French bank BNP Paribas said it has suspended three of its funds that have exposure to U.S. credit markets due to the inability to accurately value the hedge funds.

Worries about the possible spread of subprime problems were punishing European bourses. Paris' CAC 40 was losing 2.1%, Germany's Xetra Dax was down 1.8%, and London's FTSE 100 was falling 1.7%.

The iShares MSCI Belgium Index ( EWK) was lower by 96 cents, or 3.7%, to $25.63. The iShares MSCI Netherlands Index ( EWN) was falling 99 cents, or 3.2%, to $29.64. The Vanguard Emerging Markets Stock ( VWO) ETF was losing $3.33, or 3.5%, to $92.07.

ETFs related to lenders and banks were also suffering in the wake of BNP Paribas' news. JPMorgan Chase ( JPM), Lehman Brothers ( LEH), Citigroup ( C) and Bear Stearns ( BSC) all slid by 3% or more.

The KBW Bank ( KBE) ETF was shedding $1.80, or 3.3%, to $52.64. The Regional Bank HOLDRs ( RKH) lost $4.39, or 2.9%, to $146.49. The iShares Dow Jones U.S. Financial Services ( IYG) was down $3.78, or 3%, to $121.48. The Financial Select Sector SPDR ( XLF) slid 94 cents, or 2.7%, to $33.81.

Silver-related ETFs also lost ground, as silver futures tumbled 37 cents to $12.80 an ounce. The iShares Silver Trust ( SLV) was sliding by $4.13, or 3.2%, to $126.41. The PowerShares DB Silver ( DBS) was falling by 84 cents, or 3.2%, to $25.

Meanwhile, the United States Natural Gas ( UNG) ETF was jumping 4.5% as natural gas prices jumped 33 cents to $6.55 per million British thermal units. The gain comes after the Energy Department said that natural gas inventories rose by 42 billion cubic feet last week. The ETF was adding $1.79 to $41.48.

Bundled securities tracking real estate were also higher. The iShares FTSE NAREIT Residential ( REZ) was higher by $1.90, or 4.2%, to $46.73. The Ultra Real Estate ProShares ( URE) was gaining 62 cents, or 1.4%, to $46.03. The iShares Dow Jones U.S. Real Estate ( IYR) was up 54 cents, or 0.7%, to $75.14.