Investors poured more than $1.4 billion into fixed income exchange-traded funds in the past week, as they flocked to the safety of bonds, while equities markets struggled with heightened concerns over the stability of the debt-laden eurozone, particularly as it relates to Greece and Spain.

Funds like Vanguard Total Bond Market ETF (NYSEArca: BND) and the iShares Barclays 20+ Year Treasury Bond Fund (NYSEArca: TLT) were among the most popular funds this week. Flows into each ETF amounted to 4 percent and 6.5 percent, respectively, of their assets at the start of the five-trading-day period. Flows were measured through the week ended on Thursday, May 24.

That's not to say that investors shunned equities. On the contrary, U.S. equities ETFs reeled in a net of $795 million in new assets in the past week, with funds like the SPDR S&P 500 ETF (NYSEArca: SPY) leading the charge with inflows of $1.76 billion. Investors, did, however, get out of international equities to the tune of $389 million.

All in all, taking into account market action, total U.S.-listed ETF assets inched higher to $1.135 trillion, barely higher than a week earlier.

Among the largest redemptions in the week was the Energy Select SPDR Fund (NYSEArca: XLE). It had outflows of more than $1.14 billion, which amounted to almost 18 percent of its assets at the start of the five-day period. The iShares S&P SmallCap 600 Value ETF (NYSEArca: IJS) lost $365 million to redemptions, also almost 18 percent of its assets as of the start of the week.

Even gold, often thought as a safe haven in times of economic uncertainty, wasn't spared in a week marked by a flock to fixed income. The SPDR Gold Shares (NYSEArca: GLD), the world's largest physical gold ETF, was the third-least-popular fund in the past week, shedding $433 million, or 0.67 percent of its total assets at the start of the week.

All told, investors yanked more than $752 million out of commodities ETFs.

Top 10 Creations (All ETFs)

Top 10 Redemptions (All ETFs)

ETF Weekly Daily Flows By Asset Class

Top 10 Volume Surprises, Funds >$50 mm AUM

Top 10 Weekly Performers, Excluding Leverage/Inverse Funds and <1,000 Shares Traded

Disclaimer: All data as of 6 a.m. Eastern time the date the article is published. Data is believed to be accurate; however, transient market data is often subject to subsequent revision and correction by the exchanges.