Spain managed to sell €2.9 billion ($3.8 billion) in short-term debt Monday, May 14 amid strong demand but with raised interest rates reflecting investor concern over the country's finances, according to The Associated Press.

The successful debt auction came as yields for the key 10-year bonds on the secondary market - an indicator of what the government may have to pay - jumped 23 basis points to 6.22 percent. The country's benchmark Ibex stock index plunged 2.8 percent in morning trade.

The Treasury paid a yield of 3 percent to sell €2.2 billion ($2.8 billion) in 12-month notes compared to 2.6 percent in the last such auction April 17. It paid 3.3 percent to sell €711 million in 18-month notes, up from 3.1 percent. The department had set an upper target of €3 billion for the sale.