UNITED NEWS INTERNATIONAL (UNI) — Vanessa Trump, the daughter-in-law of U.S. President Donald Trump, was sent to the hospital after opening an envelope filled with white powder.

The envelope was addressed to Vanessa’s husband, Donald Trump Jr. and contained corn starch according to multiple law enforcement officials who spoke to NBC news.

Meanwhile an unnamed source told ABC news the letter had a Boston postmark and contained a note indicating the sender was angry at Donald Trump Jr.

Vanessa Trump and two others exposed were taken to a local hospital on Monday, Feb. 12 as a precaution.

The incident brought up fears of the anthrax attacks of 2001 in which envelopes filled with anthrax powder were sent to several government and media offices, resulting in five deaths.

Vanessa Trump tweeted Monday afternoon thanking New York’s police and fire department, secret service and FBI for making sure she was safe.