Categories of Martyrdom

Abu Hurairah (RA) reported: The Messenger of Allah (SAW) said, "The martyrs are of five kinds: One who dies of plague; one who dies of disease of his belly; the drowned; one who dies under the debris (of construction, etc.), and one who dies while fighting in the way of Allah."

[Al-Bukhari and Muslim]

Commentary

In the hadith above four categories of people are mentioned that are considered martyr even without being slain in the battle field. The four categories are that of a person dying in plague, dying of belly diseases, the drowned and dying under the debris (of construction, etc.). Allah will bestow them with special grace on the Day of Judgment and award them with merits similar to those of martyrs who die in Jihad. One must not delude himself into believing that by simply desiring these deaths he will go to Jannah but he should also be a true believer and a practicing Muslim. 

In another hadith:

Abu Hurairah (RA) reported: The Messenger of Allah (SAW) said, "Whom do you reckon to be martyr amongst you?" The Companions replied: "The one who is killed in Allah's way." He said, "In that case, the martyrs among my people would be few." The Companions asked: "O Messenger of Allah! Then who are the martyrs?" He replied, "He who is killed in the way of Allah is a martyr; he who dies naturally in the Cause of Allah is a martyr; he who dies of plague is a martyr; and he who dies of a belly disease is a martyr; and he who is drowned is a martyr."