Despite a 45 percent month-to-month drop in April, phishing's reign of terror isn't over yet, according to a report issued Tuesday by email security provider Postini (postini.com).

The practice of phishing involves sending out seemingly-genuine emails from e-commerce and financial institutions in an effort to gain personal and financial information from victims. This data is then used for a variety of illegal purposes, including credit-card fraud, identity theft and unauthorized bank account transfers.

Postini reports that it had deflected over 9 million phishing messages in the month of April alone. The company also found that the number of directory harvest attacks against corporate email by spammers stayed level during April, while virus-laden messages dipped by 30 percent. Postini reported processing 14.9 billion messages in April, 87 percent of which were various forms of spam. Legitimate email represented a mere 13 percent.

"The good news is that phishing attempts and email viruses declined in April. The bad news is that despite the decrease, these email threats remain a major concern for corporations, costing valuable time, money and resources," said Andrew Lochart, senior director of marketing for Postini.