BOSTON -- Three Waltham middle schoolers who police said tried to poison a teacher have been summoned to appear in court.

Waltham police said three John W. McDevitt Middle School students -- two 13-year-olds and a 12-year-old -- put cleaning solution in the water bottle of a teacher.

Police said on Nov. 12 at about 9:45 a.m., a teacher at the school said her water bottle had been tampered with. The teacher did not drink the water because she could smell a chemical in it, Waltham Schools Superintendent Peter Azar said.

It was unclear what chemical or chemicals and in what quantities had been put in the water.

The students have been suspended indefinitely, Azar said. Each student faces one count of attempted poisoning.